I'm really interested in how people live and who they really are, and how you can have an idea of someone just looking at the things (s)he buys at the supermarket or the books (s)he reads. Unfortunately, you can't get to visit strangers' houses very often, but I'm sure it would reveal more on people's personality, tastes & lifestyle than everything else.
So... I think that would be very interesting to make a collection of interiors. See what it can tell about you, whether you live in a big city or in the country, in United States or Africa. Whether you live on your own or with a big family (and a labrador)... Just see what your home says.
The point is not to show your brand new television (unless you think that your television tells a lot about you) but architecture, light, colors, details; see the differences between a flat in New-York and a parisian "chambre de bonne", just see... how people from all over the world live. You can RECord anything: photographs, videos, noises, with a description or not... oh, and no, it doesn't necessarily have to be Your home.
I think that's it... Thanks :)