Automobile Association of America
This site takes you to a local chapter site. Basic membership starts at $59/yr.

AESU Discounts
These folks specialize in discount airfares and tours.  They cater to a diverse base of ages and groups.

Best Fares Air Travel Club
Tom Parsons' club promises deep discounts on a variety of travel expenses. Membership fee: $59.90/year.

Chevron Auto Club
Benefits on basic and "gold club" levels. Services include hotel discounts and trip planning, among others.

Going Solo Travel
Singles-only club based in Calgary, Alberta. You may join their trips from anywhere. It is not a dating club.

MaxMiles
Take charge of your frequent flier miles. This club helps you track down "missing" miles the airlines fail to credit, and teaches you how to maximize the miles you can receive.

S.M.A.R.T.
Special Military Active-Retired Travel Club has 45 chapters nationwide. An avid interest in RVs and past or present military service are required.

Traveling Buddies
California-based club that organizes social gatherings for people who love to talk about travel deals. Membership is free.  

Airclub Table
This is a useful resource on the about.com air travel site. Content created by R.G. Dunham.

Airport Clubs
Business travel guide Bruce Goldberg helps you explore the world of airport clubs.