No pictures so this may be hard...I was at the Brazos between the dam and Hwy 16 catching sand bass and caught a fish that I've never seen before. It was about the same size as one of those big platter sized sunfish (about as tall as it was long) and very thin. It was silver with a blueish/purpleish tint. It's mouth was pretty small and looked similar to a carp's mouth (as opposed to a bass or sunfish mouth). I caught him on a woolly bugger fished near the bottom.

Any ideas what this was?

Sounds like a big gizzard shad.

Maybe a tilapia? Take a look and see if it looks familiar.

http://www.meadowlarkponds.com/tilapia.htm

Or it could have been a drum/gaspergoo.

http://www.trashonthefly.com/2009/10/15/gaspergou/

Hat tip to Meadolark and Long Haired Dave for the links.

Im guessing drum, or a buffalo

Sounds like freshwater drum

Did it smell like it had been left in the sun too long, and slime everything it touched? That's a black drum.

Kirk

Very thin and silver sound like a shad. The other fish mentioned are thicker and not platter-sized.

Was it really and I mean really slimey?

Thanks for the help, I think it was a drum. It did have a nasty fishy smell to it plus it's mouth looked like the fish in the gaspergou lime Txredraider provided. It put quite a fight on my 5 weight.

Thanks again