You can but its harder. Assuming you're running a PC per account go with wireless mice, use one reciever per machine and one mouse. Xzin mentions it somewhere as well using his fantastic setup (IIRC). But essentially that will work. For one PC several accounts I think AHK could be scripted to do the job but it would be fairly hard to do IMO, at the moment Keyclone doesn't pass mouse buttons (AFAIK) so that'd be out, however support apparently will be added in the future.