Sporcle has tons of timed vocabulary and trivia quizzes to tickle your brain and test your English.
Examples of quizzes:
You can browse by category (there are 15: Entertainment, Gaming, Geography, History, Holiday, Just for Fun, Language, Literature, Miscellaneous, Movies, Music, Religion, Science, Sports, and Television) and also by level of difficulty. There are apps but they aren’t free, so I haven’t tried them (iPhone/iPad = ¥170, Android = ¥187) at the time of this posting.
This one is a very good challenge for Japanese students: the names of world cities. The trick is, you are given the Romanized word in Japanese, and the name of the country in English, and you have to type in the correctly spelled name in English. I think this is a really, really good quiz for my students. Try it! And don’t get frustrated. Use it to learn the names.
Today I tried A.B. to Y.Z. and did pretty well. I missed the questions about Marvel Comics and Star Wars, and if I’d had more time I may have gotten the NFL one.