Several people have asked about what, exactly, FDIC covers and if they cover $100,000 per person, per account, per family, etc.

Luckily, the FDIC has a FDIC: FDIC Consumer News Special Bulletin (Revised September 2006)handy guide.

The relevant paragraph:

Let's say you have four deposit accounts at one institution — a checking account in your name alone (totaling $25,000), a savings account you own jointly with your spouse (your share equals $40,000), an account for a corporation you own (totaling $90,000), and your portion of an employer-sponsored profit-sharing account ($30,000). Even though the four accounts add up to $185,000, all of the money is fully insured by the FDIC because each account is in a different ownership category that is separately protected to $100,000.