Ycombinator just had their demo day where 66 startups graduated the program and pitched to investors. In addition, tomorrow is the last day to apply for their summer cycle. Some interesting ones from current batch:
Crowdtilt: Kickstarter for raising money from friends.
Givespark: Kickstarter for celebrities to raise money for charity. Started by 4 students from Yeshiva University, including S. Laks. Short article about it on VentureBeat.
AnyVivo - They sell jellyfish online. Yes, jellyfish. They dominate the online jellyfish market.
ark.com - Thye're supposed to be a good people search.
flutter.io - Control your computer using hand gestures.
icracked.com - Fix your broken iStuff.
For more info, see some of the posts on TechCrunch.