Meetup.com, I think, is best for this: by creating up-to three local affinity groups ($20 per month), you are exposed to literally millions of people who are active meetup.com participants and/or group organizers.

Since the whole thing is set-up for local meetings, with RSVP's, paying sponsors, assistant organizers, and a wonderful RSVP reminder algorythm, it is ideal for local business netwroking and creation of affinity groups of all kinds who actually meet in person, can feed an empty restaurant and lounge, and, in some rare cases, actually provide an income to the organizer!

In my opinion, for Realtors, it is a must:

Meetup.com just keeps getting better: for $20 per month, you can host up to three meet-up groups of your choosing and design. You can customize and brand your meet-up group (no that there is anything wrong about the standard interface), and the RSVP and sponsorship functions are awesome for building an affinity group of any kind. Whether your target clientele is as narrow as gay female liberals, or inclusive as everyone who drinks coffee, you can be instantly exposed to everyone in your area (probably thousands) who have indicated an interest in such new meet-up groups by key words and geographical radius.

I highly recomend this format for community building, which can integrated in on the wbpage level into any existing website, or even function as a solution of it's own.

Learn more by joining and filling out a profile for free: http://meetup.com

Guru, how are you using meetup.com?

For instance I attended a speed networking event last wednesday, recriuted a new reseller, have made three sales already!

the speed networking group could as easily been my own, or I could have spnsored it for $75