Seems like it'd be a pretty simple 3D graphics + environment/texture mapping thing. It may even already exist, I haven't looked. Would be pretty neat. Because, then, I could even show the design to others before I do it and get their feedback. They could redecorate my place, too, etc.
App number two: I'd like a really easy way to associate a photo with a geolocation. I have a photo I took at a street corner looking at a building. I have that photo on a web page. I'd like a really easy way to link to a map showing that location, and have that map have other photos taken by me or others. I'm sure there's lots of people building such things, I haven't looked. It would be pretty cool, though, if I could organize my photos by _space_ and share them with folks. I guess, they'd be pretty clumpy -- blobs whereever I've travelled. It's most interesting to me when I've done a lot of "little" travelling around where I've lived -- lots of places in Seattle or Bay Area metro areas. I'd also want to associate general geographic tags with photos -- I won't pinpoint all my Hawaii photos, but I'd be happy to say "these are all from Kauai." I guess, in the Web 2.0 spirit, I should propose there be communities, and let others in the community tag my photos ("this is really the Bank of Hong Kong building") and I theirs, and we all could have a shared map of all the photos anyone's ever taken in San Francisco / Hawaii / where ever. That would be pretty neat.
Hm, this really would be cool. Hm.