Licensing of SQL Server has always been a little confusing. Prior to installing SQL Server 2008 in your environment, you need to make sure you understand how the product is licensed. Nobody intentionally wants to violate Microsofts licensing policies. However, sometimes it is just too confusing to understand all the different licensing requirements for each SQL Server installation flavor.
Today with the people from the Internet accessing your servers, as well as your internal folks you need to make sure each individual and type of individual is license correctly. There are three different types of licenses: a device client access license, a client access license, and a processor license. Something else to consider is whether you are also setting up some kind of failover cluster. In some situations, depending on how you set up your cluster, may or may not require additional licenses. Virtual machines now days are extremely popular. If you are deploying SQL Server in a virtualized environment there are more licensing options that you need to consider.
Since there are many different installation options for SQL Server, you really need to make sure you understand how your particular SQL Server setups need to be licensed. All the different license options are discussed within this white paper. Make sure your next SQL Server 2008 deployment is licensed appropriately, by reading this white paper.