Originally Posted by Tommy Boy
Bluetooth is what you want then, it has a 30ft range.
That's entirely theoretical, and assuming line of sight. It won't work much better.
OP: What I did was get a USB extension cable, and use it to tape the IR receiver to the wall so nothing blocks it. Also, make sure you are using alkaline batteries, since NiMh ones tend to provide much weaker range due to the lower voltage.
Why are you using a keyboard and mouse? I did for a little while when I first set up my HTPC, and it was the most frustrating thing ever. I now have a gyro mouse and a mini keyboard for one HTPC, and atrackball keyboard
for the other. Of the two, I prefer the trackball keyboard, but the gyro mouse is better for gaming. I also suggest apps like remotedroid (android) or air mouse (iOS devices) which allow you to have keyboard and mouse control over a WiFi network.