Usually you’d expect a longer battery life with an add on juice pack and that’s it.  Fastmac’s lastest battery pack for the iPhone 3G, the iV, does that and yes, much more.

Sure, it’ll extend your iPhone’s talk time to 24 hours, give you 72 hours of audio playback and 20 hours of video playback.  But wait, it doesn’t end there!  Strap your iPhone into the iV, don’t touch it and you’ll purportedly get 31 days of standby time.  Additionally, the Fastmac iV includes a Bluetooth headset charger (pictured above) and a built-in flash (pictured below) for your iPhone’s half-ass 2 megapixel camera, which we all know snaps barely visible pics in low light scenarios.

Available here for $80

[Ars]