Smallbiztechnology.com calls Highrise a new CRM entrant you should highly consider.
It's feature rich and I recommend you give it a spin for your own business.Remember, Microsoft Outlook is NOT CRM. If your business is growing but your collaboration and communication tools are not, you're not maximizing technology as much as you can.
One of the neat features about Highrise is that you can attach emails related to someone by sending the email to a special Highrise email account. It's pretty neat.