i tunnel directly to my router (a m0n0wall based system) so my outbound and inbound traffic is all encrypted. there are some programs that you can use with GAIM to encrypt your messages OTR (off the record) both encrypts and provides plausible deny ability.
http://www.cypherpunks.ca/otr/win-in...otr-setup.html
oh and on sniffing, WEP is useless, however WPA will give some protection, if you have the passphrase for WPA, you still can't view other peoples traffic out of the air, this is because WPA uses a temporal key generated each time it is used. however, by arp poisoning, you can indeed sniff all traffic on the network.