http://distrowatch.com / is another good place to find linux distros.
Remember try these at your own risk. They are just suggestions for few of many choices. Caveat emptor.
Step 1: Byzantium Ad-hoc wireless mesh networking .
The goal of Project Byzantium is to develop a communication system by which users can connect to each other and share information in the absence of convenient access to the Internet. This is done by setting up an ad-hoc wireless mesh network that offers services which replace popular websites often used for this purpose, such as Twitter and IRC.
These services and web apps were selected because they are the ones most often used by activists around the world to find one another, exchange information, post media, and organize. They were also selected because they stand the best chance of being easy to use by our intended userbase, which are people using mobile devices like smartphones, MP3 players, and tablet PCs.
Unlike most mesh implementations, a Byzantium Mesh requires no specialized equipment that may not be easy to get during an emergency, just an x86 computer with at least one 802.11 a/b/g/n wireless interface. It will run on just about any x86 computer, including later generation Macbooks.