Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.

Bring - Clever shopping - simple and shared

Eventbrite - Discover Great Events or Create Your Own & Sell Tickets

Google Shopping List - Google Shopping List is a grocery list and recipe manager app that helps you to get organized and save time.

Facebook Local - Discover places to go and events happening near you

Yummly - Yummly is a recipe app. You search through lots of recipes, add the ones you like, and even create shopping lists based on the recipes you pick. You can save your recipes with one click and later organize them into collections.