I'll have a MPC to go....

I have been having to travel a lot for work lately, and can't bring the lab with me so that brings be to my question here. Anyone know how to make a power supply for the MPC and a Zip? Maybe something that is rechargeable like a lap top battery pack? I am sure I can have one made custom if somebody knows what voltage or whatever is nessessary to make it run and run safely. I don't care if it would need 20 AAA batteries that need to be changed every 2 days. I can do with out bringing the zip around, because I can use floppies while I am away. If you know, drop me a line.

my Kaboom box uses 8 D batteries and they only last like 1 or two hours, if you're trying to run an MPC and a Zip I hope you got lots of money and a strong back to carry the Duracells....