_Learned this from the Boingo mailing_
You can buy USB chargers now. Some laptops actually let you push from a USB connector and charge the battery if you can believe that, so you don't need your brick. See Advanced Accessories for Mobile Electronics (Cell Phones and PDAs) for some connectors for cell phones and PDAs.
I've been on a bunch of flights lately and some of the newer international flights have DC power using something called an Empower connector. Here the magic airplane "connector":http://shop.store.yahoo.com/laptopsforless/airpowadcor.html. that you need to connect. Costs $10, but you do need a car adapter. Magellan's also have this "Empower":http://www.magellans.com/shopping/product/detailmain.jsp?ruleID=4&iMainCat=0&itemID=618&iSubCat=0&iProductID=618&sSearch=EA270&itemType=PRODUCT for$13.
Gateway has a nice closeup of the "Empower":http://support.gateway.com/s/Mobile/peripher/6500687/6500687mvr4.shtml connector. It is Dc, so you need the right magic socket to plug in and probably a DC-to-DC convertor to go from 12V to your laptops power level. This is what a car charger does, so you need both an Empower connector and a car charger for your laptop.