Related to my previous post, I feel the need to plug Schwab investor checking. I really like it so far.
Why? It's linked to your brokerage account. If you overdraft the checking account, it pulls the difference from your linked brokerage account. No fees.
If your brokerage account uses margin, and you always have something in your portfolio, it gives your checking account some "cushion." No need to watch the balance like a hawk, since worst case you pay the margin interest rate for a short period of time until you add some cash and/or sell some shares.
Bill pay is also a feature, though I haven't used it yet.