As I have mentioned many times before and much to everyone's evident boredom, I use my computer to watch television programs: it stores them compressed on the hard disk and then outputs them to my TV so I can watch them from the sofa. Only one problem: if I want to pause the show, or select something else to watch, I have to get up off the sofa and use the keyboard or mouse to do it.
My initial solution to this problem was to get a cable extender for the keyboard, so I can carry it over to the couch, and operate the machine from there. However, this requires a lot of moving things back and forth, since I also want to use the keyboard on the computer. Also, it gets fiddly to select the next programme, since the resolution of the TV is not high enough to read off the file names.
So instead, I worked out a way of using a remote control for the computer, so I don't have to get off the couch. It gives me complete control. And it only cost $1000.
Of course, the thing is, I already had it. What I did was to install VNC server on the computer, and the client on my laptop. Now I can control the desktop PC over the wireless network from my laptop. So I have a copy of my desktop's, er, desktop, on my laptop, and can pause, select new files etc. easily from the laptop without getting off my backside. It's a vastly overengineered solution to a non-problem, which is the best kind, really.
It's also great for freaking out friends who are using your PC: surreptitiously fire up the client on your laptop, and while they aren't paying attention, move the mouse, type messages to them, or start playing songs. If they are a bit dim, it will convince them that your PC is posessed. Result!