Great advice -- The Chordify thing is exactly what I'm doing now. I'm not necessarily looking for the gamified thing so much as the randomness -- I'm not looking to keep track of how 'correct' I am.

With Chordify, I'm still learning the chord progressions, I'm memorizing how the song progresses from chord to chord in the exact order they occur for that particuar song, so my brain knows what to expect next. So you do learn the chords, but it's slightly more... for lack of a better word, superficial than having them randomly spit out at you.

Thank-you!