A Java desktop app to help you learn Riichi Mahjong yaku (hands) and scoring. Taken from the scoring quiz by UmaiKeiki on arcturus.su which doesn't really work without jumping through lots of hoops (thanks to Java's new security behavior) and doesn't even run on Chrome (since applets are no longer supported). Hopefully, will eventually be ported to Javascript to improve accessibility.
Download the application here. Just click on it and run it. Requires Java 1.6 or higher.