Sadly, there's no such thing as an ultimate buy signal when it comes to investing in stocks. Identifying companies with the wind at their back takes time, patience, and a good dose of due diligence.

There is, however, an easy way to increase your odds of finding the stocks that will beat the market. At Motley Fool CAPS, the Fool's investing community of more than 135,000 members, we've found that our "five-star portfolio" is up 15.31% between January 2007 and April 2009, compared to a loss of 40.6% for the S&P 500.

In order to fully capture the upside potential of those five-star stocks, it makes sense to identify them just as soon as they achieve five-star status. Fortunately, our CAPS screener now makes it possible to do this. Below, for example, is a list of companies that have been upgraded to five-star status from four stars just yesterday. These stock ideas are only a starting point, of course. Be sure to join us on CAPS to dig in even further.

Company

All-Stars Saying Outperform

OM Group, Inc. (NYSE:OMG)

354 of 375

Martek Biosciences Corp. (NASDAQ:MATK)

354 of 369

Harry Winston Diamond Corporation (NYSE:HWD)

357 of 373

Montpelier Re Holdings Ltd. (NYSE:MRH)

2458 of 2559

WisdomTree India Earnings Fund (NYSE:EPI)

196 of 200

Valero Energy Corp (NYSE:VLO)

4303 of 4486

America Movil S.A.B de C.V. (ADR) (NYSE:AMX)

1734 of 1767

Data from Motley Fool CAPS, August 20, 2009

Come join us on CAPS, absolutely free, to learn more about these and countless other interesting stock ideas.