Jamba (JMBA) has really performed well since I've purchased it at 1.66. I added it last week at 2.12 as well. Today its trading over 2.50 as rumors are flying that Starbucks (SBX) may be interested in Jamba. The stock still has a small market cap, without a huge float and is subject to some price swings. The pattern I've noticed since volume spiked is this: someone has been acquiring the stock. Probably a few different mutual and/or hedge funds. When their big purchases come through, they are pushing the price up pretty quickly. The stock usually pulls back once that volume slows a bit, and that is the time to add if you'd like. For example, this morning when the volume kicked up, it traded as high as 2.82, and has pulled back to 2.52 as a write. I've noticed this 2 or 3 different times within the past couple of weeks. I'll probably add to my position again on any further weakness.
I'd also add iGo (IGOI) and maybe Etrade (ETFC) on weakness.