I was planning on discussing my router hardware in another thread.
In a nutshell it's a low power Intel Atom Mini-ITX motherboard & Gigabit PCI network card with a 750G drive in a wee case. About $250 worth of gear and the free ClarkConnect Home 4.3 software (linux LAMP firewall, gateway, nas, printserver, etc...)
Much cheaper than an HP Home Server and really fast too. Draws under 40W normally with the drive spinning. It will become part of a home automation server eventually as it can be accessed like anyother website if you want. It's also just about the fastest gigabit router I've ever used.