Does such a thing even exist, aside from Tine 2.0? (which is built with ExtJS, so it feels like a desktop application - not that trilled). I've looked at 50+ systems for the past weeks, and I'm inclined to think the answer is "no".
Collabtive, Teambox and OpenAtrium don't do even basic contact management. SugarCRM doesn't do project management, and none of the extensions on their SugarExchange extensions page seem to do project management. My use case is contacts (leads) that need to be followed up with (not just sales, but leads of all sorts: press, prospective hires, contractors etc.), plus contact-independent project management (i.e. lots of research).
Basically, I'm looking for a modern, simple, functional, sleek web-based CRM + PM tool that is as easy to use as Wrike (which, doesn't do CRM and isn't open source, but among all the CRM and PM systems I've been evaluating for the past week, Wrike does project and task management most intuitively, effectively, and rapidly - see this video, for example).
I also need Gmail Contextual Gadget integration, but so far I haven't seen any collaborative PM software to do that, so I'm mentally prepared to roll my own, as long as the OSS PM+CRM software has a solid API.