I created Devoired (http://devoired.com), an academic-assistance freelance contracting site targeted toward college and high-school students. Backend is written in Django, front-end is a clean, slightly modified version of Bootstrap 2. Features include a user account system, fully editable subject tree, private messaging with support for attachments, and a PayPal-integrated chained payment system with configurable commission percentage and refund support.

Devoired currently has very little activity due to lack of marketing. Let me know if you're interested!