The LED in my magsafe connector burnt out. I wanted to get that replaced, but I figured they'd charge me for a new charger saying that it's not covered, as everyone else seems to get, so since it still charged, I figured I'd just let it go.
About a week later, my MacBook's fan would stay on constantly, no matter how light of a load I was putting on the machine, which I figured would be reason enough to take it to the store.
They figured it was the Logic board, and told me 5 days for repair, so I left my MacBook with them and headed home.
Got a call about 5 hours later that I could come pick it up. The power adapter was faulty and causing the fans to stay on. They gave me a new adapter, apologized for the problem, and thanked me for being so understanding.