I didn't know that there had been a sale on Saturday, or if a link to craigslist is kosher here, but if you search the cleveland craigslist for "40 breeder" it's there still. Call before you go, as their hours are not necessarily regular now that they've shut down.
In any case, what I found was a ton of 30 and 40 breeders, $15 each, all heavily calcified, most with damaged rims (the black part, not the glass,) and most heavily siliconed in the corners. The glass looked fairly unscratched under the crud and the fellow who helped me out was very nice. He has a few new 40 breeder tank fronts as well. Basically, if you've got more time and elbow grease than money, and you want to give building your own tank a whirl, you can get a deal on some glass. Or if you don't care what the aquarium looks like at all.
The glass is pretty crusted, and I hate to get someone's hopes up who knows more about this than I do (most people,) but it appears that the tanks that I bought were made with low iron glass. The new tank fronts that I picked up have that very dark greenish look when you look at them on edge (i.e. plate glass,) but the tanks themselves are a pale blue/aqua color on edge (low iron glass???) All have a 1" hole drilled through the bottom.
In any case, the number to call before going is 440-516-5600 between 9 and 4, m-f. They've probably got 200 tanks left at least.