Wow, I just looked at the Ars Nova website and I had no idea they had so many shows coming up. I'm working so many evenings these days it's gonna be hard to catch one for awhile, but I'll keep an eye out.
IMO, Slought Foundation (
www.slought.org) is easily one of the greatest and probably most underappreciated spots in the city. I was there last month to hear Helene Cixous, a somewhat big-name French and Algerian feminist writer, whose speaking style is the same constant, amazingly freewheeling association of ideas and words as her writing. They have music that you don't hear anywhere else. It's great to have an independent (non-university) space that has events like that open to the public.
Also please note the CEC has a new URL:
http://www.cecarts.org/