Forgive me for a slight offtopic, but I'd ask... While virtualenv is a must-use tool, is there anything like Ruby's rvm in Python's world?
RVM is Ruby's virtualenv (Wayne Seguin began work on it after Ian Bicking created virtualenv for Python, but I have no idea how much influence the two projects had on one another).
I don't use ruby a lot. Is there any special feature that you need?
Yes, there is. RVM stands for Ruby Version Manager, and in addition to virtual environments with separate sets of Ruby gems it has ability to manage Ruby versions itself.
Having one command (`rvm install 1.9.2`) is extremly convenient, not mentioning there are lots of fancy functionality (like `--static`).