Likewise - Get recommendations you love, from people you know.
Siftery - Share products your company uses and get personalized recommendations
Alternative Hunt - Learn about great alternative products as you browse the web
Stackshare - StackShare is a comprehensive website that gives its users the chance to organize and share their technology stack with the rest of the community.
SaaSHub - Find and promote software that will help you grow your business or to be more productive.
Versus - Find popular alternatives to anything in a jiffy