Best Project / Workflow Tool to Compliment Nimble

I'm looking at the writing on the wall at my company. The CRM that my company is currently using (Daylite) is most likely going to transition to Nimble at the insistence of our Business Development team. With that said, I am looking for input as to a good project/workflow tool to compliment Nimble so that way when sales comes in, work flow can be generated.

Thanks All!