one thing I wanted to add here is that these have a tendency to lose battery power fairly quickly. it was hateful to have it die in the middle of a project or chat, so I ditched it. *grin*

currently, I use a Sony optical mouse that my brother gave me (2 main buttons, with a center track wheel button). It also has a memory stick reader/writer which is really handy for transferring files. also, its not a huge mouse so fits my smaller hand much more comfortably.