The Refrigerator is some kind of awesome site run by someone obviously in Rochester, and can be visited at the oh-so-unobvious http://www.therefrigerator.net/.
While there is a ton to see, I would recommend starting with send us your cat, then moving on to Famous Rochestarians, and finally visiting the Lyell Ave section.
If you are still not full of goodness, check out the Sign Art section when you are done.
Also be sure to check out other local websites.