Yeap.. You can't tether with 3g for very long before the phone dies, even when plugged in. The phone can't charge itself faster than tethering drains.. I tried USB and the wall charger.. both the same thing, I was around 40% battery life and tethered for fun with 4-5 bars of 3g signal strength.. I fired up World of Warcraft and about 20 minutes later I get disconnected from WoW.. Look over at my iphone and it's completely dead... Battery icon showing it's too low to do anything. 5 minutes later it boots up again with 8% battery.. I thought it was a fluke and tethered again and same thing after about 10 minutes.. iPhone died. So yeah, seems the iPhone can't handle holding a WiFi connection and 3g connection at the same time - even under a charging source. I believe this to only be true when you're tethering an app (such as WoW) that has a constant stream of data and never rests... I found that if I was just surfing the Web.. it might actually gain some battery life in the interim of pausing and reading webpages. This is a huge disappointment to me.. I can't even rely on the iPhone to provide me internet for more than an hour, even when charged up to 100%. And no, don't tell me my battery is broke cause I get 5+ hours usage and 2 days standby time.. which is a lot more than a lot of people get. This is with half brightness, 3g on, and WiFi.. 50% 3g and 50% wifi everyday. My battery is more than fine. On the other hand, my phone *might* have a problem charging though.. but it charges to 100% in about 1.5 hours on a normal day... that seems pretty normal. Anybody else experience this?