So I got an iPhone 3G from eBay, and to my surprise, the battery lasted all day. Literally, all day. It'd hit 20% at about. . . 9pm, and I took it off the dock at around 5:50am. (work.) So, I did some tethering the other day (which I've done before, no biggy, 'cause our internet is cut.) Ever since that day, my phone after a full night of charging. . I took it off the dock around 7am, and it's now 10am and it's already at like, 45%. What's going on? Did tethering ultimately fuck up my battery? Or maybe something in the background is going on that I don't know about which is secretly murdering my phone battery. . ? iPhone is 3G, 16gig, 3.1.2, Jailbroken & unlocked.