I use ThoughtSaver (www.thoughtsaver.com, currently in very early beta), but most other people I know who use Spaced Repetition prefer Anki (http://ankisrs.net/

I use ThoughtSaver (www.thoughtsaver.com, currently in very early beta), but most other people I know who use Spaced Repetition prefer Anki (http://ankisrs.net/ http://ankisrs.net/). Gwern has a good introduction to the general concept of Spaced Reptition: http://www.gwern.net/Spaced%20repetition http://www.gwern.net/Spaced%20repetition