Toss it. Doubt it could be fixed and even if it could it would probably cost more than that bong is worth IMO
Well, you can fix it. Go to HD and get a glue that is good for glass. Another way to go if that doesn't work is to use epoxy putty. That can get ugly though unless you can get creative. Although we have repaired many of our glass pieces this way we did usally end up replacing them. Repairing them however, allowed us to still use them while we saved up for another piece. Good luck!