The Random Note Picker web app got a facelift and a few new features. I use this mostly for quizzing my students on their scales.
Two features added by popular request: a timer function, so you can generate new groups of random notes every few seconds hands-free, and (optional) double-flats/double-sharps.
Check it out, and send me your bug reports, feature requests, or other thoughts and comments.
Would be great if it played the notes out loud after the the timer ended to check you got them correct