For a small, young company - I would probably use Act as its only about $200 from Staples etc. Salesforce is an option but starts getting expensive as you grow. Oracle may still have a free version for a small (5) number of users which can run on a regular computer. But for the startups out there...I would use Act. Its also possible that some of the Peachtree accounting type softwares have embedded this customer relationship functionality into their software...that way you get accounting software too. Not bad.