Testing the mouse around my room, I was able to use it up to 12feet from the receiver. My room isn't huge, so I could use it in about 95% of the room. Now only if my computer was connected to a big screen TV! Also a side note, I have the receiver sitting on top of my monitor. Both are the same color, and it looks fine. You can place the receiver anywhere you want, but it has a ~ 4 1/2 foot wire, so you can place pretty much anywhere around your desk.
Review Link : Virtual-Underground