Link: Anki - friendly, intelligent flashcards

Features

  • Review anywhere. Anki lets you study on your own computer, online, on your cell phone or other portable devices like an iPod touch.
  • Synchronization features let you keep your information across multiple computers.
  • Shared decks allow you to divide work between friends, and let teachers push material to many students at once.
  • Intelligent scheduler based on the SuperMemo SM2 algorithm.
  • Flexible fact/card model that allows you to generate multiple views of information, and input information in the format you wish. You're not limited to predefined styles.
  • Fully extensible, with a large number of plugins already available.
  • Optimized for speed, and will handle reviewing decks of 100,000+ cards with no problems.
  • Clean, user-friendly interface.


Open Source
Operating Systems:

Windows
MAC OS X
Linux
FreeBSD