[aschen]

They have these tiny booster packs these days, which I might consider a good alternitive to jumpers

Amazon.com: Brightech™ - SCORPION - Car Jump Starter and Battery Charger for Electronics and Mobile Devices with Carrying Case - Ultra Large Capacity 10,000 mAh - The Ideal Portable Power Source To Keep In Your Car, Never Be Stranded By a Dead Batter