They're all copyrighted the moment they're created and published. The copyright isn't a *registered* copyright, but it's a legal one nonetheless. People will steal them regardless, and it'll usually cost more in legal fees to prosecute them than you can ever hope to get back from a settlement. I've been dealing with intellectual property theft online for 15 years, and there's really no good solution. However, we could start putting "ClutchFans.net" somewhere over the graphics where they can't easily be removed -- that way, at least if someone steals one for their site, it might drive some traffic back in this direction. Damn, I see that T-Mac "Second-Round Virgin" poster all OVER the net.
Yea, my own damn fault for not putting some sort of watermark on that. It pissed me off seeing it in the hands of a Jazz fan during the playoffs.