I have a bot running a similar amount of hash tables RusselB. Do you know how to calculate how much memory is being used by hashtables?? I've had people cry to me that some of my scripts that use hashtables are slowing down their computer. I have a machine that's running two mirc bots with a combined 21 hashtable scripts and it never complains.
It's a P3 with only 256MB of ram ;/