Pension Funds -- the Next Shoe to Drop

In addition, the company is also on the hook for the missing amount. The PBGC will only step in to manage a pension plan that is closing and is fully funded, or in the case of a bankruptcy.

Some companies have opted for stronger quarterly earnings rather than the proper funding of their commitments. Some assumed an average yearly return of as much as 9%, a short-sighted move.

Public funds, such as Calpers, and state employee and teacher funds nationwide most likely will have similar-sized shortfalls, requiring help from the states, whose reserves are already running on empty.

When looking for companies to scoop up at a discount, investors ought to scour reports for the time bomb of pension underfunding. ConocoPhillips, Macy's and Viacom are all rated "hold" by TheStreet.com Ratings, while GM is a sell. With pensions in peril, the ratings probably won't improve for some time.