Linux turned 20 on Aug. 25

The first Linux distro I played around was Red Hat Linux 5.2 in 1999.

After that, I backed to Windows for both professional development and personal desktop application usage. Before that I developed a FoxBase+ application on SCO/Unix in 1990 for a year. I tried again with another distro in 2002, I guessed. Still not a right time, back to Windows. Today, I'm using Ubuntu Linux on daily basic. I'm still using Microsoft Windows for software development (ASP 3.0, ASP.NET, C#, Microsoft SQL 2008, IIS 7, TFS) at work. Anything else, Linux. Android development: Linux. Web develop using PHP, Python, MySQL: Linux. Desktop word processing: Linux. Web browsing: Linux. Listen to music on computer: Linux.

Microsoft SQL Server

When someone mentioned about Microsoft SQL Server, we thought about money. How much to pay?  Actually Microsoft offers two free versions: Microsoft SQL 2008 R2 Express Edition and Microsoft SQL Compact Edition (CE) 4.0. Developers can use Microsoft SQL 2008R2 Express Edition or Microsoft SQL CE 4.0 for prototype, development, and testing.

Microsoft SQL CE 4.0 is an embedded SQL server database engine. It can use to build standalone and occasionally connected applications for mobile devices, desktops, and Web clients. The maximum database size is 4GB per file.

Microsoft SQL 2008 R2 Express is a free edition of SQL Server ideal for developing and powering desktop, web and small server applications. It can support up to 10GB, 1 CPU and 1GB RAM.

Other paid Microsoft SQL 2008 R2 editions such as Standard, Enterprise, or Data Center support up to 524PB, more than 1 CPU and 64GB RAM, and much more features.

Reference:
Compare Microsoft SQL Server Editions
VS 2010 SP1 and SQL CE - ScottGu's Blog
Everything SQL Server Compact