MSR's PocketRocket backpacking stove is ultra lightweight and super efficient.  You won't even notice it in your pack.  It's precision flame control, that's glove friendly, goes from torch to simmer while the wind shield boosts efficiency in breezy conditions.  There's no need for priming, pressurizing, or maintenance and it will boil a liter of water in a little over three minutes.     
 

Minimum Weight    3 oz / 85 g
Packed Weight    4.2 oz / 119 g
Burn time (MSR IsoPro) per 227-g / 8-oz. canister    Appx. 60 minutes
Boil time (MSR IsoPro), 1 liter    3.5 minutes
Water boiled (MSR IsoPro) per 227-g canister    16 liters
Water boiled (MSR IsoPro) per 1 oz. of fuel    2 liters