Not sure what everyone else thought he would do going into the season, but Jake Delhomme was vastly under-rated in my 12-team league. I think he was around the 10th or 11th QB taken - I was planning to platoon him with Pennington, but that didn't quite work out. Largely because Steve Smith has been excellent, Delhomme has put up big numbers for me almost every week.
Other guys (some have been named already):
Plaxico, MEshawn, Galloway, Griese (until he got hurt)