OtterBox, makers of waterproof cases for PDAs has announced the oPod for 3rd generation iPods, reports iPodlounge. The oPod case features an “interactive water resistant membrane,” access to the headphone port, buttons and touch wheel, though there’s no access to the Hold switch. The US$49.95 oPod, slated to ship next month, will be available in five colors. Pre-orders are now being accepted and will be entered into a $20 iTunes Gift Certificate giveaway.