Depending on your computer specs, SymLinking might be of benefit.
Multiple accounts on one PC sometimes greatly benefit from this.
It's worth checking out, the Search function from the main page will find it.

Jamba addon, from the macro/addon forum is immensely helpful too.
Keyclone has pretty good tutorials on his site: www.solidice.com/keyclone

The dual-boxing.com community rocks.
The more information you give, the better we can assist you.