NetHunt CRM - Turn Gmail into a smart CRM
Immediately - Mobile sales email and CRM management for Gmail & Salesforce
Streak - Manage customers inside Gmail
Pigeon for Gmail - A powerful CRM and automation suite built inside Gmail.
Evercontact - Your contacts always up to date and automatically with Evercontact.
Followup.cc - FollowUp for email is a lightweight productivity suite that keeps your conversations and tasks from slipping through the cracks. Set perfectly timed reminders that arrive at the top of your inbox, right when you need them.