Streak
Streak is a tiered customer relations management system with three primary levels of service. The first level is entirely free, and it is geared toward individuals who need more personal CRM solutions than larger corporate or enterprise level brands. Despite being entirely free, the most basic level includes unlimited private pipelines and more than 200 tracked emails per month. Their second tier, the Corporate level, is their most popular option since it includes the full suite of CRM tools found in Streak. The highest level is their Enterprise tier, and it includes specialized utilities that are only needed for businesses at that level. The sophistication of Streak is such that it can meet the needs of just about any business, and it drastically reduces the amount of organization and data tracking that must typically be done in the sales process. There aren't many CRM systems with the same level of versatility.