Crystal litter does seem to really work at keeping the smell down. Who knew? Certainly not me. It's pricey, but the benefits are worth it.
Finally, the past few nights it has sounded like my frisky felines were playing soccer with a ping-pong ball. Today I discovered that this is because they WERE playing soccer with a ping-pong ball. I took the ping-pong ball away and hopefully will be able to sleep better.