I have a half a dozen sheets of 3/8" Glass. I don't know much about the glass - whether it's tempered or not, but it's definitely in good shape, would need to be cut.
Most of the pieces are at least 4 foot by 3 foot - $15 a sheet
If you're interested in them please let me know - I'll also trade for Corals or General Equipment. Looking for a Mag Drive pump, Short T-5 Setup/Ballast.
I can give exact measurements and/or photos - not sure if there's anybody out there that's looking to build a tank or Sump baffles.