I run a home server (hey, I'm a geek), and I use an old PC for the task. It's doing a sterling job, but it's big and noisy and hot, so I got to thinking about how I could improve things. I really want something small and cool and quiet with an Intel processor, so a Mac Mini would be ideal, but they're kind of pricey for something that will be a glorified file server.
Whilst looking about for an alternative, I recently stumbled across Mini Koobox, which is an interesting product. Koobox sell Linux PC's with Linspire pre-installed, and the Mini Koobox is a small-footprint machine with a Celeron-M or Pentium-M CPU. The price seems OK, too. That said, it's just not a Mac Mini ;)