Know of a good free lightweight python IDE?

I want a good IDE for developing python when i'm out of the office. We use proprietary software there and i'm not interested in buying a program if i don't have to. A good eclipse plugin would be nice, but I have a net-book who is not a big fan on the super bulky eclipse program, so something more lightweight would be better. I work with a bunch of java developers so none of us know a ton about python/jython....