Can Android do peer-to-peer ad-hoc networking?
Here's a bug report on the feature you're requesting.
It's status is "reviewed" but I don't believe it's been implemented yet.
Although Android can't find and connect to ad-hoc networks it sure can connect to Access Points. So as a work-around you can turn your Wireless Card into an Access Point using, for example, Connectify.
my friend and I are currently developing a java library implementing the AODV protocol (multihop routing suitable for mobile networks), in our bachelor thesis. The final 'product' includes a easy way to create/join an adhoc network on several android devices and an interface through the library, to send and receive messages. Unfortunately each type of phone such as hero, nexsus one... have a phonedepended way for createing a adhoc network so currently we are only supporting a few phones).
this means that once this project is finished, people with rooted phones can implement their distributed applications (file sharing, games, ...) by simply including the library .jar file in their android projects.
it's all open source by the way