bwahaAHAHAHHAH!
SATAN: Oh saddam, why can't we just talk, you know like we used to?
SADDAM : Relaaax GUY!!!
You know what comes next...
But I wouldn't wear a T-shirt with any kind of slogan or picture, I'd just keep catching it out of the corner of my eye and find it distracting you know, plus to be honest i'd consider it kinda like an advertisment saying: "look here, I'm just letting you know in advance that i'm an idiot!!"
But you could make a 'lil statue of your angry granny and put a sound chip in it, make it so you put it on the dashboard or office desk, and every few minutes it just randomly farts, frowns, then shakes it's head in disgust at it's own flatulence...
One of the funniest hings I ever came into contact with was this 'lil yellow vinyl beanbag, with a face drawn on, and when you squeeze it, it begins to laugh, then the laughter grows, and finally becomes hysterical, and it's so infectious that you hold it to your ear and laugh with it. The beauty of it was, that no-one else could hear the bag, so they just see this guy holding a bright yellow soft thing up to his ear, laughing hysterically... Heheeeheee I'm laughing now just remembering that thing
ZX Spectrum 48k Issue 3, Radio shack Tape drive, Rank arena 12" T.V. set.