The Meetup Events module provides a way to automatically sync events created in your drupal site to meetup.com. This assumes your definitive data about your events lives in drupal, but you'd like to have the events also listed in meetup to get more publicity.
Through the administrative UI you configure syncing to meetup on a per content type basis. Each content type specifies the date (and optional venue / lat / lon) fields to sync to meetup. There is also a body field which uses tokens. To increase the power of those tokens, installation of notification_content (to get node-body) or the included nodereference_tokens (to get body tokens for referenced nodes) is encouraged.
Contributions are welcomed to evolve this module to meet the needs of more people.