stayed at the McGill Royal Victoria College dorm room for 50 dollars. Shared bathroom. Right near the campus and a quick metro ride to anywhere. Great museums nearby or hike up to Mont Royal.

I stayed at Bishop Mountain Hall twice in August, and was very satisfied. My room was very clean on both stays, no complaints there.

A few things I did not like were:

The cafeteria shuts down breakfast at about 9:30 or so.
Rooms on one half of each building housed men, and the other half housed women.

There is NO air conditioning, although the windows open a fair bit.

The last time I was there, I was in McConnell room 436, and there was a bright floodlight that is used to light the field at night that was left on until late one night, even when no one was using the field, and I had to call security to have the lights shut off.

Other than that, I had a very pleasant stay.

I actually thought that this was better than the Crowne Plaza (now the 'Plaza Hotel Montreal'), where I had a horrible experience. It was certainly a $46.01 per night well spent.

Wow, what can I say about the McGill Summer Residences? Fantastic location, at the foot of Mount Royal, on the corner of Sherbrooke & University at one of the country's most prestigous universities and only a 5 minute walk from Ste-Catherine St.
I stayed at Royal Victoria Hall in June and got a fantastic room for only $40. Lots of cabinet space, free 24 hr internet terminals in a common room and free internet connection in the room if you have a laptop. Also, the best thing, your own personal mini-fridge! Wow, great.
Stay here and you'll be able to explore Montreal no problem...just a 2 min walk to the metro.