SwitchEasy is best-known for cases, but the portable battery pack Tanks ($70) is company's first foray into electronic accessories in many years. The 6000mAh cell supports 2.1A charging, meaning it'll charge all iPods and iPhones at full speed, and some iPads at full speed as well. Without a doubt, it's one of the most interestingly shaped batteries we've seen; instead of a box or a tube, the glossy plastic is molded around the shape of the cells,…