A year and some months ago, I was presenting to you a fuel cell designed specially for the Army, the XX25. It was fueled by methanol and it had a capacity of 25 watts lasting for 8 hours.
Now, I found out that the company that produced the XX25 methanol fuel cell from last year, Ultracell, came up with an improved version of it, the XX55. This fuel cell outputs 55watts at 4 amps (10-30 volts), and can last for days or even weeks on a single methane cartridge.
The powering device is also accompanied by a power management module, that automatically manages outgoing and incoming power from its 6 powers. For example, with a managing module you can run a laptop, radio, laser designator and a battery charger while also adding power from a solar panel, a 12V auto battery and other power sources.
The XX55 was designed for the army, like it was with the XX25, so the price is a little prohibitive for the average Joe. The fuel cell costs $10,000 and each methanol pack costs you $35. In campaign conditions, one would find it very useful, but if you just want to go to a picnic around town, the expense is a little too much.