You may disagree, but I believe it is a good practice to cluster all the SQL Server instances. That is, even when you plan to run a SQL Server instance on a single machine, you should install it in a single node cluster. The primary advantage is that...(read more)

http://ns2.sqlblog.com/blogs/linchi_shea/archive/2012/02/10/clustering-every-sql-server-instance.aspx