Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
Mapiful - Create & order custom printed maps of your favorite places
Facebook Local - Discover places to go and events happening near you
Grafomap - A map poster of your favourite place on earth
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Craft & Oak - Beautiful, minimalistic custom map posters