I work with a small marketing and design company. We host some of our client's websites/email when they don't have a solution in place. It's a favor, not a money maker. We also have about 10 employees - not a 24/7 helpdesk.
One client had his Outlook settings set to erase messages off the mail server when they downloaded to his inbox. He then left his home computer running, went traveling, and called me to ask why he couldn't receive any emails using webmail.