WaniKani is an online Japanese vocab and Kanji learning service which uses spaced repetition. Great for those who are studying Japanese or are aiming to sit the JLPT (WK apparently covers a large amount of the JLPT vocab / Kanji / daily use Kanji).
Have used it for just under a week now and love the interface and find it a fun way to learn. They do a once a year sale - I bought it as it should be a good way to keep my kanji / vocab level up :)
I already did a Wanikani before logging onto the internet, thanks for checking.