That badboy is pretty good... I like that it gives you the proper fingerings.
I'll have to fart around with that one...
I know I've put this up here before and I love this site, especially as it gives you the note intervals (though you need to build the fingerings with the intervals, which may twist some people up)
but this is the site I've used with much success
chord house ::: guitar room (advanced) -- online guitar chords and scales
The on-the-fly tuning change is pretty nifty too....
And I havn't mentioned this but I have a copy of the Guitar Grimoire: Scales and Modes, for people who don't mind having a hard copy scale book... it covers quite a bit and provides you with Conventional and Sweep patterns(makes building your own arpeggios a synch) and covers full range modal shifts for a ton of scales.