I have a 50 lb piece of very cool texas limestone that was used in an african cichlid tank until I set up the reef. It DOES fit into a 55 gal and is a very nice rock. I'll be able to send a photo in the near future. In the meantime, check out this photo:

http://pg.photos.yahoo.com/ph/slik_dude/detail?.dir=/5301&.dnm=cc27.jpg&.src=ph

Its the big rock on the left.

I also have some old dead coral to be used as decorations in salt or fresh tanks. Contact me for a photo.

I'll trade for anything reasonable.

BR