By weird I mean outside of regular cat diet, things like cornflakes, ketchup or banana bread (these are real examples from my and my friends' cats).
Does "his own vomit" count? I found him behind a table munching and crunching on something. Turns out he had thrown up there at some point, it went unnoticed, dried, and he was eating little dried bits of chewed up "party mix" snacks.
Really, this seems efficient. Recycling.