SugarCRM

Hmm. Maybe as an enterprise competitor to Salesforce. Otherwise, I'd say Base CRM or Nutshell are more product hunt worthy. (If they haven't been posted, someone plz post) In my interaction with Sugar CRM, I was disappointed in their lack of pricing details (not common in SaaS space unless your goal is to charge high prices) - and they'll only support a minimum of 6-8 seats to start last I checked mid 2015. Not super startup friendly. Even Salesforce has upfront pricing and can start with one seat.

CTO @sugarclint made Sugar to be a pretty slick CRM. Integrates with just about everything and makes customer services easier through tracking.