I've been to a few of the Bo Forbes classes at Yoga on the Square - they're a little advanced, but I liked them a lot. Unfortunately I think she won't be teaching there for long. I went to one of the hot yoga classes a few months ago and I liked it too, though I needed a long nap after! Quirks of the space are - big mirror on the wall and sometimes you can smell Redbones BBQ.

I've also been to a few of the gentle yoga classes at Karma Yoga, a few blocks from Harvard Square. Lots of good core work and a very nice space with a cafe in front. I'd like to try some other classes there too.