I have Pdanet 1.61 on my iPhone 3G. I've been using Pdanet since version 1.3. I've noticed that while it works great, it seems to drain the battery something fierce. I have it plugged into a wall charger, and with Wifi tethering the iPhone still drains the battery, though MUCH slower than if it was not plugged in. I wonder if USB Tethering doesn't drain the battery as much. Any thoughts?