Exist - Track everything in one place, understand your life.
TechEvents.co - Tech and startup events aggregator
Zenobase - Zenobase helps store and visualize data.
Facebook Local - Discover places to go and events happening near you
Swarm - Swarm lets you earn prizes and compete with friends based on the places you go.
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets