Mophie is scheduled to begin general shipments of their extended battery for the iPhone 3G starting October 31. Unlike their prior offering, this version is going to allow syncing through the charging cable – so long as you use a different style charging cable than the default one shipping with your iPhone. While I’m definitely not keen on another cable to keep track of, mini-USB cables are pretty common and it will be nice to sync while charging the extended battery. We previously reviewed the first generation Mophie here. As an iPhone user who typically runs out of juice by early mid-day (2pm-ish) I can vouch for the need for an extended battery. Cost is $99.

Mophie Juice Pack for iPhone 3G via Engadget Mobile and Crunchgear