Service Management is the new hype in both local and global companies. It is all about delivering services that support business needs instead of just showing them how to use file sharing and outlook. Service Management requires Help Desk software among other things to be able to register support requests, incidents, change, and problems and so on. These software solutions are most often very expensive and quite cumbersome to configure. For global organizations, an expensive service management solution could be the way to go, because they will be dependent on vendor support, but for smaller ITIL based organizations, open source help desk software is adequate and much cheaper. One of the best solutions is a PHP helpdesk system that can be modified to fit almost any organization and since it is open source, it is the PHP programming language that sets the limit for how much you can customize the software. If you already have a PHP based intranet and have experience with either ITIL 3 or ITIL version 2, this software is very easy to implement and can be managed by a single employee.
If you are in need to a service management product that are not open source but still cheap, I suggest you look into Heat Help Desk. Because of its price, easy of use and customization options, this tool is a very good competitor to the open source selections.