The folks behind Mobcharger are talking it up as a solution to the all-too-common (?) of running out of cellphone battery life just when you need it most, like when a bear is chasing after you. If your cellphone's battery dies, plug in the Mobcharger and you'll be able to talk for up to 90 minutes, or leave on standby for 480 minutes. It comes in different models for the myriad cellphones (one for Samsung phones, one for Motorola, etc.) and requires that the cellphone in question already have been charged at least once before. It's expected to retail for less than $10 or thereabouts.
Product Page [Mobcharger via The Red Ferret Journal]