@Mor - I'd love to find something like that. Most of the vacation travel clubs I've found seem to be catering to demographics that I don't really fit in with. They are either after the very young, the very old or families.
I'd love to have a travel club membership where the people in it were more interested in doing things like visiting historic sites or doing aid work overseas or something like that.
I guess the next best thing is to just do package deals that include a group of people and hope that I get on with some of the people in the group.