Controlling a TV-connected Boxee media centre from a laptop is easy with the Boxee Remote widget, but it only runs on Macs. Unless you use Kludgets, which seamlessly brings the widget to your Windows desktop.
Lifehacker reader Pablo told us that this neat work-around worked for him on Windows XP and Vista, and we've tested it on Windows 7 as well, where it ably controlled a Boxee media centre on Ubuntu. Install Kludgets and run it, download the Boxee widget, and then select "Open widget package" from Kludgets' right-click menu. Point it to the Boxee remote widget ZIP, and it'll run.
You'll need to click the little "i" in the lower-right to point the remote at your Boxee setup, but after that, it serves as a pretty handy control for when you're doing the simultaneous laptop/video thing. Thanks Pablo!