I actually was challenged that and I made a fairly good one. It was early on in my gfx career so it's kinda crap, but it's alright. It's not COMPLETELY text... more like text and color...

but anyways, if you're going to do a full out text sig, it'd be a good idea to proofread. It's defense, dude. Just lettin ya know

Otherwise, I think these are actually pretty nice. They're not exactly your typical sig with a stock and effects and stuff, but if it's a full out text sig, it needs a little more ingenuity.