Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
KeywordTool.io - KeywordTool.io is the best FREE alternative to Google Keyword Planner and Ubersuggest. It uses Google's autocomplete feature to get over 750+ long-tail keywords for any given query.
Event Hunt - Startups and Tech Events Curated By Locals
Google Trends - Explore Google trending search topics with Google Trends.
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Keywords Everywhere - Free browser add-on for keyword volume, CPC & competition