Didn’t he once eat a care box from his mother like 15 years after the fact or something?
All his paraphernalia from the Hells Satans motorcycle gang
There was the pier he ate after being kicked out of the all-you-can-eat buffet. Have you ever looked at a pier? The underwater bits have all kinds of nasty smelling mud, algae, barnacles, petroleum byproducts, and other things stuck to them.
[Lionel Hutz] Does this sound like a man who’s had “all you can eat?” [/LH]
Homer’s Mom: Son, you don’t have to eat that 15 year old candy just to make me happy!
Homer: But it wouldn’t make you unhappy, right?
He found a turkey he’d left behind a bed in a motel a week earlier and ate it while singing:
Oh Margie, you came and you gave me a turkey. On my vacation from workey to the tune of Barry Manilow’s Mandy
Has he ever tasted Selma’s delights? - now that would be disgusting 
Meh. I’ve eaten lipstick.
He once ate the “candy” bride and groom from the top of a wedding cake (turned out to be plastic, of course). Not as disgusting as some of the others in this thread, but it looked very painful.