Here is a sweet root-fifth voicing....
C-G-C \ E-B-E
If you put both hands together, they make a Major7th chord. Play with this voicing, when you need to play either a Maj or Major7th chord.
Here is the minor7 version....
C-G-C \ Eb-Bb-Eb
I'll post a clip of some uses for these chords later....You can move it diatonically though. It's really effective, when you're going from 1 to 4 or 1-5, diatonically.