Watch the Rapid Fire - Rhythm online guitar lesson by TrueFire from Play Rock Guitar 8: Advanced Rhythm Principles
Rapid Fire - Rhythm - Variations is a video guitar lesson presented by Jeff Scheetz and is sourced from Rock Solid.
You can change this up by trying different types of chord shapes as the chords change.
The nice thing about this is that I am using "partial" chords, or just two notes from a chord.
This really gives you a lot of options because you can find those two notes on many different strings and change the voicing and sound of the changes by experimenting.