Like the other guys have mentioned, I would suggest foam over cork. One very good foam popper is the Gartside Gurgler:

Tying the Gurgler

Another great (but lesser known) fly is Capt. Bob Marvin's "Happy Face" fly. Scroll down here for a pic:

Fly Fishing Insider Newsletter featuring The Fly Fishing Shop - Snook

And here's another pic:

http://i194.photobucket.com/albums/z...r/DSCF4341.jpg