For plenty of financial advisers -- who also serves as quasi-therapists, spiritual gurus and confidantes -- Monday was bad.

Really bad.

The S&P 500 posted its largest drop -- more than 6 percent -- in nearly three years, sparked by rising fears of a recession and fueled by the United States' loss of its perfect triple-A credit rating. Panicked selling on heavy volume resulted in the S&P's worst day since December 2008 -- every stock in the benchmark index's components ended the session in negative territory.

An adviser at a brokerage giant Merrill Lynch office in a Philadelphia suburb said the phones rang off the hook all day.

Thank goodness for people who are on vacation and not calling in, although many are, she said, asking not to be identified by name due to company policy. Every call is too long. Tons of emails. Everyone doing conference calls, which are pretty much worthless.

She turned down the television volume several times and thought about putting on the Food Channel.

Alan Haft, an independent financial adviser in Newport Beach, California, said his phone was buzzing with calls from clients wanting to sell everything.

One calls saying the Mayan Calendar is coming true, that he's absolutely certain this really is the beginning of the end of the world, Haft said.

The eight money managers at Capital Investment Advisors in Atlanta started their day with an emergency 8 a.m. EDT meeting to review the situation. The good news? We don't think this is 2008, said Mitch Reiner, chief operating officer at the firm.

Reiner said more aggressive clients took advantage of cheap prices, adding Intel , Procter & Gamble

, Eli Lilly and other large-cap dividend stocks to their portfolios.

But one very conservative client wanted to know he wasn't among the bargain hunters. Reiner's response: Because you can't handle being down 3 percent.

Trying to talk people off a ledge is never easy. Several advisers said it was even more difficult on Monday because they already talked clients off the ledge last week when the U.S. debt deal was sealed.

But several advisers who focus on long-term financial planning say their phones were quiet on Monday.

Richard Coppa, managing director at Wealth Health in Roseland, New Jersey, fielded just three calls from clients, which honestly, is a good sign, he said. And the clients he did connect with are disgusted with our government, more than anything. Added Patricia Powell, a certified financial planner at Powell Financial Group in Martinsville, New Jersey: It is deadly quiet. I have not received a single client call or email about the markets today.

One theory is that financial institutions are panicking more than retail investors. My inbox is getting flooded with their take on the market slide, ratings downgrade, etc., said Ori Pagovich of Gotham Financial Services in New York. Everyone either has a Webex, Webinar, white paper, update or anything in between on the events of the last two business days.

With every big downturn comes opportunity, though.

While clients are certainly concerned about recent market activity, they are not panicking; some have viewed the current pullback in the market as a potential buying opportunity, said Joe Jennings, investment director for PNC Wealth Management

in Baltimore.

Monday was one of the heaviest trading days at ING Direct Investing . All told, the firm processed about 50,000 individual orders, which amounts to about 100 per minute, said Dan Greenshields, president of the ING Groep NV unit.

And there were more buyers than sellers who snapped up Apple and General Electric , along with several exchange-traded funds, such as SPDR S&P 500 , SPDR Gold Trust and Powershares QQQ Trust .The bulk of that buying came from individuals aged 21 to 39. People with long time horizons are buying, Greenshields says.

Margaret Black-Scott, who is president and CEO of Beverly Hills Wealth Management, has been talking up Coke , Proctor & Gamble and Johnson & Johnson to her clients. It's a variation on the mantra know what you own coined by Peter Lynch, the legendary manager of the Fidelity Magellan Fund.

Take a look on your pantry shelf. What do you have there that you have to have? said Black-Scott. Do you drink lots of tea or coffee or eat breakfast cereal? There are lots of things we don't need that are nice, and then there are lots of things we have to have.

(Edited by Jonathan Oatis)