Meetup - Helps groups of people with shared interests plan events and facilitates off line group meetings in various localities around the world.
Really Good Emails - A large collection of good product email design.
Eventbrite - Discover Great Events or Create Your Own & Sell Tickets
Good Email Copy - Email copy from great companies.
Bigtent - BigTent is a web-based organization and communication portal for groups.
Good Sales Emails - Best sales emails from great companies