HubSpot CRM - Free CRM software for small businesses.
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Less Annoying CRM - A simple customer relationship manager made just for small businesses. Manage contact info, track leads, and never miss a follow-up.
OutlookTime - OutlookTime is a time tracking system that turns Outlook into a timesheet system.
Keap - Grow Sales. Save Time. Get Organized.
SendBoard for Trello - Receive and reply to emails in Trello