Una última opción que puedes evaluar es
SQL Server 2005 Express Edition
"Similar" a SQL Server, sin algunas de las características avanzadas de éste y con algunas limitaciones (
...it is limited to using a single CPU and up to 1GB RAM, with a 4GB maximum database size. SQL Server Express does not include any of the advanced components of SQL Server including Analysis Services, Reporting Services, Data Transformation Services, and Notification Services.)