This place is brilliant--the staff are helpful and patient and they definitely know their stuff. I went in planning to do a few small repairs that I didn't have the tools to do at home (tighten my brake cables, replace my brake pads), and ended up learning how to true my wheels and replace my brake cable altogether.
It's not really a bike shop, so don't go there expecting it to be--they don't have a regular stock of bikes for sale and they don't seem to carry accessories like bike helmets and bells. They do have a supply of parts, though, both used and new (used parts are pay-what-you-can, while new parts have set prices), and of course, all the tools you could possibly need to fix your bike.