Lately i've been foolin around with the vai multi string tap and yngwie
sweep picking. Then it clicked do both together. If u sweep say an A minor 14-13-12-17 ( i wish i had a tab program sorry) tap the c (20th fret) with your middle finger. then move positions down to d minor 10-10-10-13(tap 17) then i plug in the vai technique. go down to G major 7-8-7-10-(tap 15) then tap on the b string 7-8-7-15 on the high e 7-10-7-15 and alternate those fast. fool around with those 2 techniques and some really sweet melodies will arise. Have a good day gentlemen.