That sucks. Hopefully thenewgreen's advice helps, if it doesn't maybe you could let some homeless person live there temporarily so they have an opportunity to get back on their feet?
I like this. I like this a lot. We're downtown and I get hit up for help at every corner. Just take one guy I feel I can trust aside and give him the key. Leave my air matress and some blankets. "Have a month out of the cold, friend."
A better (?) -- more feasible -- step might be to post around on your location's reddit, craigslist, whatever stuff like that you have access to, looking for someone who's in desperate straits for whatever reason and really just needs a roof for a couple weeks. Grabbing the nearest homeless guy might accomplish the same thing, but it might not work well. If you can at least get a friend of a friend or some slight personal connection, it'd be safer and easier. Just a thought.