If you're looking for something even simpler, and cheaper, than a Mac Mini for basic computing and perhaps some living room-related duties, eMachines is happy to oblige you with the new Mini-e ER1402 small-form-factor. You won't get much in terms of fancy specs, but it does come with its own pedestal -- and only costs $299.99.
Instead of going the Intel route, like the Shuttle X350, the Mini-e uses AMD's Athlon II Neo processor, which is coupled with 2GB of RAM, 160GB hard drive, and Nvidia GeForce 9200 graphics. You also get an HDMI port, so you can hook it up to an HDTV. You also get a wireless keyboard and mouse, but you don't get any kind of optical drive -- the Mac Mini doesn't come with a Blu-ray option but does have a DVD burner. But the eMachines system costs a lot less if you already have a standalone Blu-ray player, plus it produces a "a soft ambient green glow along the lower edge." (Oooooooooo...) If you don't want to show off the Mini-e on its pedestal, you can also mount it behind the monitor or TV to which it's attached.
Though eMachines is listing the price at $299.99, only Amazon is currently selling it for that price online. You'll pay a little more at Newegg ($309.99).