In case you hadn t noticed, Twitter is everywhere these days. The social-networking phenomenon has attracted endless amounts of publicity, with celebrities ranging from Oprah to Ashton Kutcher now beaming out the ultra-short updates known as tweets.

But can Twitter help you invest? Increasingly, financial types from economists to actual traders are blasting out their thoughts on Twitter (always in 140 characters or less, of course). There are also free sites like StockTwits.com that compile Twitter postings on financial news, individual companies and broader market issues. Some of the updates are compelling but as with so many other forms of digital communication, there s a lot of dross out there, too.

See Paul Krugman and 11 other pundits you should check out on Twitter.

So SmartMoney went in search of financial tweeters worth following. To narrow down our list, we talked to avid users of Twitter, scoured university economics departments to find out who s tweeting and of course, spent hours reading money-related tweets.

If you haven t tried Twitter yet or are relatively new to the concept, get started with guides here and here

Here's our list of 12 financial Twitterers worth following. Want to share your opinions or tell us who's on your list? Send us a tweet @kellibgrant.

Nobel Prize-winning economist, currently a professor of economics at Princeton University and op-ed columnist for The New York Times.

Twitter handle: @PaulKrugman

Followers: 6,676

Why follow: Not exactly prolific, Krugman s most recent tweet as of this writing was more than six weeks ago. (His last post was March 11.) Still, given his influence in economic matters, some fans -- and critics, too -- will want to follow him just for the chance of early warning on Krugman s thinking. Krugman did not respond to requests for comment.

Sample tweet: "The Obama administration s economic policy is already falling behind the curve. [Links to New York Times column.] Posted March 11, shortly after the administration released its first budget proposals.

Denver-based trader and author of Technical Analysis Using Multiple Timeframes.

Twitter handle: @alphatrends

Followers: 5,320

Why follow: He may not be a household name, but Shannon is gaining traction among the trading crowd with tweets that include his stock investment moves, videos and webinars. Shannon says he s careful not to include exact dollar figures about what he s buying and selling. I don t want people to follow me I want them to use [my posts] as a learning tool, a springboard for their own ideas, he says.

Sample tweet: Short-term volatility is greatest at turning points and diminishes as a trend becomes established. ~ George Soros. Posted April 22, just before the market had a particularly rocky session.

Former hedge fund manager and current day trader based in New Jersey.

Twitter handle: @upsidetrader

Followers: 4,677

Why follow: Donohue includes his real-time investment moves and market observations, with a few personal tweets mixed in. He says he started Twittering when posting nightly updates on his blog proved less effective in communicating his trading strategies. It seems to have made me a better trader, he says. With so many people looking at what he does, Donohue says he's more cautious about the moves he makes.

Sample tweet: breaking on bberg-wow-ken lewis said under oath that Paulson and Geithner told him to low key the problems at bac/mer-dumb it down baby $. Posted April 23, shortly after the news crossed the wire.

Contrarian economist (also known as "Dr. Doom"), a professor of economics at New York University s Stern School of Business and chairman of economic consultancy firm RGE Monitor.

Twitter handle: @Nouriel

Followers: 3,633

Why follow: First and foremost, Roubini is credited for accurately predicting the current recession back in 2006. His tweets include links to articles and blog posts that cite his views. The account also tracks his comings and goings from economic conferences and speeches where he offers observations on the market. Roubini declined to comment.

Sample tweet: has written a new paper on China. [Links to RGE Monitor report.] Posted April 9, shortly before Roubini left to attend the Boao Forum for Asia, where government leaders and business officials met to discuss international cooperation to stem the global financial crisis s effect in Asia.

Economist and chairman of private equity investment firm Rutledge Capital, which has invested more than $150 million in manufacturing and distribution companies.

Twitter handle: @johnrutledge

Followers: 2,400

Why follow: Updates on his travels and television appearances. Also tweets about his thoughts on economic and market news. Rutledge often solicits input from followers, asking them if they have questions for the Chinese government officials he was meeting with (including Premier Wen Jiabao) and what business ideas they have that need funding. Rutledge did not respond to requests for comment.

Sample tweet: am at BOAO Forum. 14 heads of state in one room this morning incl China Premier Wen, Pres of Pakisan and Iran sitting at same table. cool. Posted April 18, during the three-day Boao Forum in China.

Founder of Seabreeze Partners Management in Palm Beach, Fla.

Twitter handle: @DougKass

Followers: 2,116

Why follow: Kass posts just once or twice a day, keeping his tweets to the topics he finds most substantive about the market at that time. I prefer not to tweet all day, he says. He also links to columns and blog posts at TheStreet.com, where he s a contributor.

Sample tweet: i am moving to a slightly more bearish short term position now $$. Posted April 22, during a mixed session in the market that led to a late selloff.

Founder of Kentucky-based investment firm Tatro Capital, with $10 million in assets under management.

Twitter handle: @tickerville

Followers: 1,857

Why follow: Market impressions and forecasting tweeted mostly after-hours and over the weekend. Tatro s big project: Tape Talk, an audiovisual presentation that posts three times a week. He also hosts StockTwits Brunch on Saturdays during which he and others tweet about the market s performance during the previous week, and what they expect in the week ahead.

Sample tweet: Surprised by futures dump? Shouldn't be, major resistance ahead. $$. Posted April 20, before the stock market dipped below 8000 for its worst day in six weeks.

Former Major League Baseball pitcher for the Toronto Blue Jays and other teams, and former Merrill Lynch broker.

Twitter handle: @ToddStottlemyre

Followers: 1,854

Why follow: Daily trades. I really try to keep it to what I m doing that day, says Stottlemyre. Short tweets help him engage with other users to discuss which stocks are hot, and talk through trades. But he s quick to admit that not every trade gets posted. The people who have followed me have learned that I can be in and out in a very short period of time, he says. That doesn t always make it up.

Sample tweet: if finnies trade higher tomorrow, $bac will be my first go to trade in that sector. Posted April 21, the day the Treasury Department disclosed that it had added Bank of America (BAC) to its mortgage modification incentive program, with the bank set to receive nearly $800 million.

Professor of business administration at the University of Alaska, Fairbanks.

Twitter handle: @WayneMarr

Followers: 1,480

Why follow: Roundup of insights from economists like New York University s Thomas J. Sargent and University of Chicago s John A. List (neither of whom Twitters). Marr, who served as senior economist for the Securities and Exchange Commission, says he s been trying to figure out which tweets are the best conversation generators. One tactic: throwing out controversial studies or comments to his students and other followers.

Recent tweet#economics Do you agree?. Posted April 23, posing the question to his students.

Professor of economics at George Mason University and author of Discover Your Inner Economist.

Twitter handle: @tylercowen

Followers: 470

Why follow: Short reviews, and notes on quirky market and economic indicators that don t make it onto Cowen s blog. I am very much a fan of Twitter, but I think usually a person's posts don't make sense except as part of a longer dialogue or with a good amount of background context, he says.

Sample tweet: Still wondering why na[t]ive art traditions around the world have as many common elements as they do. Posted April 10. (One of Cowen s specialties is economics as it pertains to the arts.)

Director of marketing for Morningstar Financial Communications.

Twitter handle: @lesliebanks

Followers: 434

Why follow: Financial news that impacts advisors (and consumers, too), like the discovery of the latest Ponzi scheme and snapshots of stock earnings. Banks also uses Twitter to keep in touch with financial advisors who subscribe to Morningstar, often asking them for their feedback through surveys. Content comes from Morningstar, as well as a variety of other sources like Investor s Business Daily and The McKinsey Quarterly. Banks usually includes her own take on the links as well.

Sample tweet: Reading: Hanging Tough, discusses benefits & long-term impact of marketing & acquisitions during recessionary periods. [Links to New Yorker article.] Posted April 22.

Vice president and chief currency strategist for FXDD, a forex trading brokerage firm.

Twitter handle: @gregmikeFX

Followers: 131

Why follow: Market news and commentary on global economics -- anything that could affect foreign currency markets is fair game. A newcomer to Twitter, Michalowski says he decided to experiment after seeing CNBC s tweets scrolling across the screen during market hours.

Sample tweet: Can Retail Sales stronger. USDCAD holds support. [Links to FXDD chart.] Posted April 23, as an explanation for performance of the two currencies.