Keyclone isn't free though $20 per pc, but it is for life and the Rob (the guy that made it) is always on the forums and is every helpful.

You lucked out, today someone wrote a really good write up on Octopus (i believe it is free) which is another option that you have.
Multi-boxing Part 1: Getting Started

I went keyclone and i think it was the best $20 i spent, but then again i never used the others. The others might have a little more programing and setting up to do. With clone i was up in 10 minutes.

Just a little hint, if you have trouble setting it something up (send Rob, keyclone, a pm if you are using keyclone) please read the wiki and sticky that are here and do a couple of searches. Cause people tend to get a little mad when the same question is asked for the 100th time.