I am returning to Mojiti again. I think it is a great potential resource for language learning. John has also played with it. As John points out it can be a little time consuming particularly at first but I believe it makes a great tool in the learning Chinese arsenal. You can create your own little excercises and projects and at a level that suits you, these are far more powerful and interesting than any homework you might be set in a class or an excercise from a text book.
My next Mojiti project is to finish transcribing the following video, I figure if I post it here I will have to finish it (I have been rather busy recently and only made a quick start so far). I will be fairly hard work, although I know what she is saying (a least a pretty good idea) that is not the same as being able to write a character by character transcript, there are a few areas I am going to find quite sticky. Transcribing in Chinese is most important for me then I will do an English translation set like I did with the last song I did. Basically she is talking about the definition of beauty, the proliforation of beauty products, chat shows talking about dieting beauty products haircuts etc., beauty product adverts, changing yourself this way won't provide deep lasting happiness, if she changed her eyelids (I think) it wouldn't make her any happier in the long run, friends and family will love you for what you are, everyone has their own personal beauty etc. etc.
When I get round to finishing it I will put a transcription on my study materials blog also. This is the nearest thing a self learner like me gets to homework.