I'm planning to build a community-driven website with voting functionality similar to StackOverflow (or Digg etc..). I really like SO's voting system where your points are deducted for voting down someone and so on.
Anyway, is there any open-source module/component available that I can plug into my app directly without having to reinvent the wheel? The app will developed probably be in PHP or Python.
Thanks for your comments and advices.
Try this its written in PHP ZendFramework
phpancake http://sourceforge.net/projects/phpancake/
A questions and answers system, where the validity of the questions and their answers is determined and moderated by the community by a voting system. This open source system is on the lines of Stackoverflow and digg.
Have a look at Pligg
Pligg started as a simple CMS to let users submit and vote on news articles, and that's still what we do best. Vote on stories that interest you and articles that receive enough votes will appear on the homepage of your Pligg site. Pligg offers a 5 star method for voting or the more traditional numbered voting as seen on sites like Digg, Mixx, or Reddit.
There are a few for Django:
Personally I've only used django-voting. It has a nice section on using it for a Reddit/SO style voting including templates and using Progressive enhancement: http://code.google.com/p/django-voting/wiki/RedditStyleVoting
I think the other projects have some interesting features in terms of custom ranking/sorting methods which is where django-voting can fall short.