One of the things I hate most about NiCds (yes I'm still running them until my LiPo comes in the mail) is how hot they get on the charger when they near the end of their charge. I have thought about pulling them off the charger when they're done and sticking them in the freezer for a few minutes, but I have a rather bad feeling about it. Is this ok to do?

I would not recommend it. Many used to run a cooling fan on their NiCD or NiMH packs while charging/discharging but sudden extreme temp changes aren't good.
The pack will actually perform better while it is warm [not HOT] off the charger. Anything over 125-130 degrees F and your charger is probably going past cutoff and overcharging them.

Charging at a lower amperage will help the heat issue somewhat

I wouldn't recommend it either - the temp is part due to IR heating and part due to the chemical reaction taking place during the charge. I wouldn't want to cool them down artifically worrying about messing up that reaction and ultimately the performance.

If peak temp is over ~130F, you need to back charge rate down a little.

Ok, thanks for the info guys. What sort of C rate would be a safe bet for charging?

Unless you're racing, there's no need to go above 1C. Racers would charge above 1C, but they didn't care about packs lasting more than a few weeks either.

Thanks Duster! Jeez, you help me out a lot on here