Hubspot’s Free Sales Hub CRM is seriously powerful. Whether your business relies on a longer sales cycle or you’d just like to centralize info about your prospects and customers, Hubspot can help. And it integrates with almost everything.
I use it for maintaining my contacts and my to-do lists, and to get daily email reminders about sales and relationship activity.
We also use it at one of my companies as a literal hub of all information throughout the lifecycle of our contacts’ accounts.