Here is an interesting photoblog:
Sigma Phi Epsilon Houses
Yup, that's it. Photos of most of the SigEp houses from around the country. I don't know who put it together but he (she?) has way more time - and apparently a much larger travel budget - than I.
There are also links to several other fraternity and sorority house picture blogs. I'm sticking this on on the sidebar for reference. Be sure to let the author know if you have pics of houses that are not shown or updated from your own house.