Too bad it doesn't support Microsoft CRM - would be a great platform to run it on. Like the guy says it costs a LOT to scale out with MS-SQL, and Server Licenses
Microsoft SQL Server Enterprise Edition retails for $24,999 per physical processor.
MS Server 2003 Enterprise R2 retails for $3,999
(granted you can get these for much less than retail prices but still expensive as heck) We have a system with 2 Dual Core processors so that would cost us $50,000 just for SQL 2005 if we went that route.
MS SQL 2005 Pricinghttp://www.microsoft.com/sql/howtobuy/default.mspx
MS Server 2003 R2 Pricinghttp://www.microsoft.com/windowsserver2003/howtobuy/licensing/pricing.mspx