There is fabric that you can print directly onto (can be found at Michael's).
When I was making stuff for punk friends (I was never really punk myself), I would've loved that.
Also if you go to fabric stores they frequently have leather remnants (especially upholstery-type fabric stores) for cheap. Lots of fun stuff can be done with leather remnants.
edit: oh wait even better, I just read about this. I've never tried it though. Get sticker paper (like for printing stickers), take the back off, and stick it to any old (FLAT, tightly-woven) fabric. Then feed that through the printer. Muslin et al works best. It's a little cheaper than getting the special stuff from Michael's.