In an attempt to provide a good language learning tool, the Language Learning department of SIL has been looking at Anki and various Addons to provide a good tool for learners:
Anki is a popular flashcard program. Their website says:
Anki is a program which makes remembering things easy. Because it's a lot more efficient than traditional study methods, you can either greatly decrease your time spent studying, or greatly increase the amount you learn.