just got a 12v and 13.2 (switchable) bike battery which is a lithium-ion. i have wired the end to an XLR connection and then to a 'y' XLR splitter, to power the hd-p2 and the mini-me. we've even got another splitter to run into the m248, but rarely need it that badly.
anyways, it is a small 5.2maH lithium ion. bright blue light, waterproof housing, and a nice locking cable to splice to.
from batteryspace.com, good deal.
it ran my rig at RE:Generation for 6hrs, on one charge. i ran it on 13.2v mistakenly so i think i drained the power quicker than normal. i'm gonna try 12v for 7hrs this weekend.