If you are not using a decent CRM system, now is the time to consider Microsoft CRM. CRM 4.0 is a good product, and CRM 2011 (to be released shortly) is a great product. Microsoft has really added some useful technology in the new release.
We use Microsoft CRM extensively to help manage our technical support activities and new sales opportunities; and to a lesser extent, our marketing activities. But we are using it as a key part of our automted service delivery for www.myGPcloud.com
You should also consider connecting it to your GP system using the CRM Adapter for GP. The out-of-the-box integration touch points are depicted here:
Here is a short video from Microsoft on the subject.
