We are looking for a new solutions to power our Mac powerbooks and Leaf backs on-location meanwhile shooting tethered.
So far we have used a gas generator but it's heavy and a less mobile option.
There are a lot of battery options on the market but we need a solution that can keep going all day and can power laptop, DB, FW-powered harddrive an optional a small printer.
I'd consider a sealed deep cycle battery and pure sine wave inverter.
You could easily mount the two items in a small cart (think carry-on suitcase size) and recharge from the main/grid or from a vehicle. A sealed battery would eliminate the need for fuel/noise/fumes and could be transported by plane if needed.