I called up my local micro-brewery and asked if I could have some leftover yeast for homebrewing. They were really cool about it and said yes.
I dropped off a sanitized mason jar and picked it up later that day. It was nice and full of active pale ale yeast.
It's currently in primary fermentation, it's one of the most vigorous and sustained fermentations I've seen.
Yeast prices are nuts right now at my LHBS, and I bet this stuff will be way better quality.
FYI, another local brewery I called was NOT into this idea at all and acted rather snide about it. Anyone calling your local brewery should prepare for different reactions from different brewers.
It was definitely worth it, since now I have a reliable hook-up for the best yeast I could hope for!