I came across this great site to learn a bunch of useful stuff. Ever seen those memory champs who can memorize a pack of cards? Well these guys have come up with a great site to help people use those same techniques to learn languages and other cool stuff. I have been using it on and off for a few months and have found it very useful.
This is a useful website, but beware of the fact that it does not always 'count' accents when marking your spelling - a missed accent does not equal an incorrect answer.
Also, as all the courses are created by volunteers, there is a range of quality. One course I used had several spelling mistakes (in the French) which I recognised but which, even when I contacted the course creator, were not rectified.
But it is based on sound learning principles and is pretty good, for a free website. Just don't rely on it as your only source of language acquisition - I use it as more of a 'top up' to develop my vocabulary.
I love memrise's concept, I have been using it for a little week (192 german words planted/learnt!).
It does say in the FAQ "There is a course database setting that allows strict typing mode to be turned on—this enforces every character being correct though, on case as well, so may not be suitable for every language course."
I used memrise a couple of years ago before going to China, to learn some of the characters. It really helped when we went to a local restaurant and I could at least identify which dishes were beef, chicken, fish or dog...