HubSpot CRM - Free CRM software for small businesses.
Propeller CRM - Small business CRM with deep Gmail integration
Keap - Grow Sales. Save Time. Get Organized.
Cloze - Smarter Relationship Management
Less Annoying CRM - A simple customer relationship manager made just for small businesses. Manage contact info, track leads, and never miss a follow-up.
Highrise - Save and organize notes and email conversations for up to 30,000 customers and contacts. Keep track of proposals and deals.