E-mail trouble is the most common reason employees flag down the IT team. An in-house e-mail system requires a robust server. And floods of spam and system crashes can consume hours of technicians' time. Estimates put the monthly cost of maintaining an internal mail server -- including license fees, bandwidth, upgrades, and the staff to run it -- at as much as $50 per employee. That's why many businesses are switching to hosted options from companies such as BlueTie, FuseMail, Everyone.net, and Mailtrust, which can cost as little as $1 to $15 a month per user. Many offer hosted Microsoft Exchange servers so you don't have to get used to a new program, or they offer Web-based programs that look similar to Microsoft Outlook. Most provide around-the-clock customer support.