GrowthList - A crowd-sourced list of growth hacks
100 in 100 Challenge - Get 100 new paid users in 100 days
ScrapBook - ScrapBook is a Firefox extension, which helps you to save Web pages and manage the collection.
#buildinpublic - Discover what people are building in public
Do Things That Don't Scale - Discover new unscalable ways to grow your startup
FIRST - Post a date, pick a winner & meet up.