MAN, do I feel your pain right now. Had surgery for a knee condition on my right knee when I was 16, got used to favoring the knee, and BAM - left knee goes out. I am also on the "no exercise pending surgery" bandwagon, and let me tell you, it SUCKS....and I have to wait until Sept 13th to even get the operation done, then the 4 week recovery...
The only thing I've been doing is upper body lifting...it isn't my regular cardio, but it IS better than nothing. Also, when I'm on crutches, it'll make it a heck of a lot easier to get myself around if my arms are super strong. Other than that, it has been a major challenge to not do ANY kind of my regular cardio, and it is seriously depressing. Just wanted to send lots of

and tell you that I completely understand what you're going through.
I'm also in the sleepless-because-of-knee-pain club right now. Lately I've been trying to fall asleep with the knee elevated and iced. I know you're not technically supposed to leave ice on the knee that long, but its the only way that it stops hurting, and this has really helped me. Still hurts like heck in the morning, but at least I can fall asleep fairly well.