Unfamiliar vocab flashcards!
I'm currently making flashcards as I try and improve my Czech by reading news articles etc. with unfamiliar words. It would probably be more useful for people who have completed the Czech tree, although it may cross over if I don't remember a particular word when I come across it, but it won't be comprehensive (both as it's a work in progress and I know some vocab from Memrise/Anki that doesn't come up on the tree)
I hope this helps some of you!