Here are a couple suggestions. Feel free to use them exactly as they are, or put your own twist on them, or just come up with your own.

T-Shirt Hell: Irony and sarcasm can go fuck themselves

T-Shirt Hell: It's the other thing the internet is good for (porno images)

T-Shirt Hell - In case you hadn't guessed, we sell T-shirts, dumbass

Hitler looking at a computer and he has a thought bubble that says "That shit's fucked up" w/just a little TSH logo in the corner

Jesus saying "Shirts with the F-word?! That shit's fucked up."

left to right scale captioned "The Awesome Scale" - starting at left it has lame stuff like "The Bible" and "Consent" somewhere in the middle is "T-Shirt Hell" and a couple things after that on the more awesome side like "Fisting a bum" and "Pancakes and Meth"

T-shirt Hell t-shirts: Buy 'em for family, coworkers, neighbors... You know, anyone you never want to talk to again

T-Shirt Hell shirts: Because beer-making sex-bots don't exist yet (w/pic of something like that)

(pics of guys kissing all over banner) T-Shirt Hell: We just made you look at dudes kissing (or T-Shirt Hell: Producer of the world's gayest banner ads)

Little crossword puzzle that has 1 across as "Kick ass T-shirt company" and 1 down is "A fat cunt" or whatever insult and the answers are at the bottom as T-Shirt Hell and Your mom.

Spoof of one of those "Which celebrity is this" web ads - and it's just a pic of someone like Hitler or Jesus or George Washington w/the bar across the eyes, and it has multiple choices like those ads - A. Margot Kidder B. Frank Zappa C. T-Shirt Hell - or just make all the choices weird celebs and say "Wrong, it's T-Shirt Hell")

T-Shirt Hell shirts (pic of drunk guy w/puke dribbling down his chest) You'll probably get puke on them

Your mother's a drunken whore - Buy a shirt to get your mind off that

Show kittens or whatever animal being fed into meat grinder and show shirts coming out the other end T-Shirt Hell.com

C-U-N Hell - C-U-N-T-Shirt Hell that is www.tshirthell.com