Dave Northey has created a really great screencast on EDGE which shows you how to configure a cheap three node cluster using ISCSI ( basically intercepts SCSI commands and shares them over the network ) across three Windows Server Core machines managing file sharing.

This experience is all carried out using 3 x Windows Server Core to act as the cluster to support the File Sharing Service and demonstrate the failover capabilities.

Go to the following link to see some more details of just how easy this is.

http://edge.technet.com/Media/Windows-Server-2008-Failover-Clustering/