Right now OtterBox primarily offers two lineups of phone cases: the Impact series, which are lightweight skins, or the Defender series, which has three layers to protect from splash, scratch and impact damage. The problem with the latter is that is adds considerable bulk so you really need to mean business if you’re going to clamp on a Defender case. Well, OtterBox has threaded a fine needle and created a hybrid style called Commuter, which lets you remove and reattach a hard outer shell on an as-needed basis. That kind of flexibility is really handy for people who only occasionally operate in rugged conditions, or sometimes need added pocketability. In order to pull this off, they’ve basically turned the Defender series inside-out; instead of having a hard plastic core surrounded by the rubber skin, they’re putting the skin on the inside, which makes more sense if you’re travelling with a stripped-down version. The first devices to get the Commuter treatment are the Nokia E71, E63, BlackBerry Curve 8900 and Storm, all running for $34.95. We’re going to try to give some of these puppies away next week, so stick around!