Consider Avidian Prophet
You might want to consider Avidian Prophet. I purchased it but the press of other obligations has thusfar kept me from installing it and converting customer records over to it. I learned about Avidian Prophet from posts in these forums, so you may want to do a search on it here.
Prophet works from within Outlook and appealed to me since it's not yet another application that I have to have running. And should we ever outgrow it (an unlikely event since Avidian claims that they have clients with over 300 seats using it) I'm guessing that the data should roll into the Microsoft Dynamics CRM, or nearly any other CRM out there since Outlook is a de facto standard.