I installed Canola, Mediabox and egg-timer on my N800, and now my wife uses it as a multimedia device in the kitchen with small external speakers. Our guests get amazed with how good the N800 is at that. We can even watch the BBC on the N800 while preparing a meal.
In one small device we have a FM radio, a media player, the weather, Internet radio, a UPnP player (video and music from me Lacie server), a kitchen timer, a clock (Cairo clock), and when needed we can do IM.
N800 used for bittorrent downloads to save power, no need leaving a bigger box on 24/7. Last week installed webserver so now able to update / test my sites while away from an open internet connection.
Also use the mplayer daily for music and surfing to sites that are blocked from work (ebay/ paypal etc.)
If you watch Netflix Instant movies on a tv, you have to add the films you want to watch to your instant queue on the Internet. You can do that most easily by having an N800 near the tv. In my case, this saves me a trip upstairs where the computer is.