If you look for "big & tall" stuff at a costume store, options are pretty limited.
|That's about it.|
Elvis? You're fat Elvis.
Indiana Jones? You're fat Indiana Jones.
Darth Vader? You're the guy who ate Darth Vader.
Batman? Go ahead and make the obvious punchline yourself.
The point is, I find it best to abandon the whole pop culture scene and look to areas more philisophical and existential for inspiration. Personally relevant and easy to do are factors also. As a result, THIS is my Halloween costume this year...