Yes! If the audience can't tell, I do a lot of trading-card type things. I found something called "Artist Trading Cards" in a local art supply store about a year ago and I've been mildly obsessed ever since. Mostly because I prefer smaller works. The bigger the canvas, the more uncomfortable I am. Don't know why.
But at any rate, they're basically blank cards (the exact same size as all other TCs from Yu-Gi-Oh to baseball cards, apparently there's a specific size you have to be no matter what) made from a variety of media so you can use them no matter if you're a painter, a cartoonist, a sketch..er...whatever! You make unique works of art on them and then trade them with other artists who also have done cards. You're not REALLY encouraged to sell them...
Yeah, but my plan is to go to a con with card that I've done and masses of blank cards. Then I would have given away the blank ones and begun the trades! Heh. They're actually rather inexpensive, about two fifty for 20-odd cards, so the only obstacle I have to overcome is actually MAKING it to a con...heh heh...