Regarding audio files.. I did some playing with text-to-speech programs last night and found an easy way to generate a reasonably small audio file for each question. I'm attaching an example here. It's a 10k MP3 file. So if I could find an easy lightweight way to play these and mix them with player output, we could have audio questions. However, 20,000 questions * 10k = 200 megs. Not sure anyone would want to download that much.