By using a powerful boost converter anyone who has 3s - 5s RC LiPo packs can build a mobile laptop charger.
This is a simple enclosure for the following boost converter: http://www.ebay.de/itm/231530770443?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
Simply adjust the voltage potentiometer to the desired voltage which is about 20V for most notebooks and solder the appropriate connectors and wires. Since this converter has a constant current option for driving LEDs, the current pot has to be wound up until max so that the curent is not limited.
The device is run well below its max specs and barely gets warm, so you can print this in PLA as well. I used some drops of hot glue to secure each wire after mounting the PCB into the enlosure.