Whether spinning elaborate tales of their cartoon selves or staging semi-virtual live shows, Gorillaz have made the art of machinations their business. What’s turned them into more than a digital hat trick has been their tunes. While not exactly new material, D-Sides offers a double-CD set of early demos, remixes, and b-sides, which should hold fans over ’til their third LP. As always, the best Gorillaz tracks breathe a bit of rock swagger into these catchy electronic ditties, like the previously video-only release “Rockit,” where slow, drawling basslines glide into a lazy strut for the nonsensical “blah blah blah” vocals. Now if only the animated ones would drop some new tracks–that would be the best caper of all.