It was the novelist and critic Alison Lurie, I think, that coined the term 'legible clothing', to describe anything with either a logo or slogan on it.
And haven't we had some lulus? Oh hohohoho...
I AM A VIRGIN (and this is a very old T-shirt)
KEEP DEATH OFF THE ROADS... DRIVE ON THE PAVEMENT
NICE ONE SQUIRREL (cartoon of shagging squirrel)
MAKIN' BACON (cartoon of shagging pigs)
PATIENCE MY ASS... I'M GONNA KILL SOMETHING
GUTROTTIN ETC PEPSI
More to follow, if anyone can bear it