Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
Slack It - A bookmarklet to share links in Slack with one click
Facebook Local - Discover places to go and events happening near you
Slinky - Your slack links — organized!
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Top Daily Hunts in Slack - A simple, fast way to browse news within Slack