We use "media PCs" -- regular computers in the role of media appliances -- instead of conventional electronics like TVs, DVD players, and TiVo boxes. I'll probably describe our whole setup in a future post, as well as sketch out the trials and tribulations of running a multi-node MythTV setup.
Recently the DVD drive in our living room computer has had trouble reading a lot of discs. I think it's worn out. I tried rummaging for a DVD drive in our housing complex's electronics recycling pile but didn't find anything, so I'll probably order the cheapest drive I can find on Newegg.
This made me realize a hidden benefit to using media PCs instead of consumer electronics: it's possible to repair and upgrade computers. Consumer electronics like DVD players are not designed to be serviced and replacement parts are not available, so if we owned a regular DVD player instead of our media PC we'd have to throw the whole thing away and buy a whole new DVD player (about $75 new). Instead we only have to discard a 5.25" DVD drive and buy a new one (about $20 new, and easy to find used or even free).
When I set up our media PCs it seemed like a pure extravagance, but it turns out that we exchanged a need for "throwaway" products for equipment that can be maintained easily and cheaply. So maybe using maintainable equipment like old PCs is defensible even when it's overkill for the task at hand.
I wonder if this is true in other areas -- for instance, using an industrial-grade stove or clothes washer that's designed to be kept in service for a long time.