Houdini the hamster reached two years old; none of the others we’ve had ever quite made it to that age, but so far he still seems to be going strong.
And no, we only let him lick the cake, not eat it :). He’s probably at least half-way to being diabetic just from being a two year old hamster.
He’s definitely more sleepy than he was a year ago, but he’s still running around the house in his ball and running in his wheel at night when we put him back. He’s also learned to knock the webcam off his cage if we put it there to spy on him.