How about some arcade style challenges or record keeping for those that would find it interesting or fun to bring out the competitive nature in all of us.
I just completed an unusually long run of successful pinyin reviews and finally missed one. I was curious about how many I got and how that compared against previous records. To be honest, what with my recent discovery of the "eccentric" toggle, I half expected a high score/combo hit count, a la Street Fighter. Then, I thought, hey, that would be pretty cool.
Then I thought how fun a larger Arcade style set of games might be.
Any thoughts, suggestions, brainstorms?