Hitchhiking a plane

Sometimes hitchhiking on a plane is possible. Attempting this from large commercial airports is likely impossible. The case may be different in rural areas, or from smaller airports on the outskirts, or in the suburbs, of larger cities.

Some general tips:

Every medium-sized and large city will have small airports, often on the outskirts or in the suburbs. Look up airports in the phone book. Airports which offer flying lessons will probably be good ones to look for.

If the airport has a small coffee shop or restaurant, hang around there and make conversation with pilots (recognizable by flightbags and jepsen charts--small chart-holders which strap onto the knee or upper thigh, leaving both hands free). Obviously, acting like you're interested in flying will help your case!

Offer to wash planes--the going rate is around $50, or ask to come along for the next trip. Be prepared with a bucket and sponge, and feel comfortable asking where the spigot and hose are. At really small airports, planes which get flown a lot look like it--dirt streaks, flat grass around the hangar.

Often pilots looking to up their airmiles (for increased certification, etc) will make routine weekly flights to cities several hours off by car. Be sure to ask if they're planning on landing!

Inexpensive Flights

airhitch.org seems like someone's money making scheme. But if you have some experience with it, please write about it... Wikipedia has some more information, article and talk page.

airtech.com is reputed to be a better, less scam-y seeming, company.

skybus.com, which offers a very limited amount of destinations, has a handful of $10 tickets per flight; tickets rise in price as more are sold. All flights are routed through Columbus, Ohio, meaning that each leg of the flight is $10 or more.

You might have more luck hitchhiking a boat.