What exercise can I do?!

MoeNificent

So I used to be an avid runner...until knee surgery. The surgically repaired knee is still not near 100% and now the other knee is almost as bad. So running is out. I can't afford the gyms around my area (already doing jenny craig...just don't have it in the budget). I don't have a lot of room in my living room to do exercise videos. I do a lot of walkign because I don;t drive. But that's really my only exercise. Any suggestions?