Showing up to the 1999 Academy Awards in dresses (and as revealed years later, having dropped acid on the limo ride over). Additionally, any time any reporter asked about their choice of attire, the pair always responded with something generic and unrelated like y'know, it's just a magical evening... Trolling at its finest.
Abusing the tolerance of Comedy Central's legal department (yet again) on the Imaginationland DVD commentary just because they can. Knowing it will give some poor Standards & Practices official a heart attack, they frequently go from relatively intelligent insight about the episode then suddenly segue (in the same sentence, no less) into what can only be assumed is hilariously vulgar/slanderous things about any given celebrity or religion, which is always immediately dubbed over with the outro credits music.
Trey: But um, actually right now we should talk a little about Tom Cruise and Scientology... [a solid 30 seconds of music] ...raping babies. And now back to Imaginationland.