My father asked me a few weeks ago, during the market turmoil, if he should sell his ExxonMobil (XOM) holdings. He's been amassing a small fortune in Exxon over the years by taking part in their Dividend Reinvestment Plan (DRIP). Although S&P knocked Exxon down to 3 stars I told him to stay long oil and after last week's record earnings and profits for 2007 he plans on doing so.
I'm a big believer in holding selective companies for the long term, especially in DRIP accounts; I currently own C, XOM, INTC, and T in several brokerage or DRIP accounts. You have to remember, what's out of favor now will become in favor at some point in time. Buy quality companies when no one wants them and sell/hold them when everyone wants them.
Its so simple and Zen like, yet we hardly ever do that.