Fat Lama - Borrow stuff you need. Lend stuff you don't
Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
Daylui.com - Daylui is an "Airbnb for everyhing else".
TechEvents.co - Tech and startup events aggregator
Idle - Rent Any Thing - A Peer-to-Peer Renting Community for Idle Goods
Facebook Local - Discover places to go and events happening near you