Give away free name badges to organizers of meetups to make it easier to remember other members' names
Give away free name badges to organizers of (new?) meetups. Monetize/pay for it via paid ads on the badge and/or put the Meetup.com logo on it. This will both be a good source of revenue and brand the Meetup.com name and the members will benefit since it will be much easier to remember the names of the other members.