I keep thinking I'll make a portfolio for some stock site, but I always say "oh, I'll wait until I have the photo from *next thing I plan to shoot*..."
I probably have enough generic sports shots as well as landscapes to submit by now, so I'll see. Maybe when I get my new gear and get some good BMX/MX shots with fill flash, and some field sports. I'm not going to be able to compete for product shots with my $20 'studio', so I won't try.

http://flickr.com/photos/madman2k