The Windows CE Shared Source Premium Derivatives Licensing Program gives access to source code for Windows CE 3.0, Windows CE .NET and Windows CE 5.0, plus future Windows CE versions as they are released. The program "... allows licensees to create derivative works of the source code to improve, optimize, and debug Windows CE. Licensees can use the code as a reference to develop enhancements to Windows CE and provide feedback to Microsoft about improving the Windows CE code base and development tools."
Who is eligible for this program? The person or business entity must reside in one of the eligible countries, be a device manufacturer who has licensed over 5,000 Windows CE run-time licenses during the previous 12 months, or:
Windows Embedded Premier Joint Development Partner
Windows Embedded Silicon Vendor Partner with one or more certified Board Support Packages (BSPs) for Windows CE
Windows Embedded Partner Gold-Level Systems Integrator
Microsoft Most Valuable Professional (MVP) (I am in this category).
On the other hand, the Windows CE Shared Source Licensing Program "... allows developers to use the Windows CE shared source code for developing, debugging, and supporting Windows CE-based devices at no cost. Additionally, OEM customers worldwide can create and distribute commercial derivatives of the Windows CE 5.0 operating system source code for shipping in commercial devices without notifying Microsoft or sharing their derivative works with the embedded community. A valid Windows CE 5.0 runtime license must be purchased for each Windows CE 5.0 derivative work prior to distribution."
The main difference between this program and the Shared Source Initiative is the technology platform covered and the scope of the program. The Shared Source Initiate gives access to Windows 2000, Windows Server 2003 and Windows XP source code.
If you develop smart applications for Mobile Devices using .Net Compact Framework there is another program, called Smart Devices Developer Samples Source Licensing Program that may interest you. The licenses are just a click away and allows "... developers and other interested parties [with a rich set of technologies that enable them] to build applications for smart devices. The program permits licensees to use, modify, and redistribute the licensed source code samples for noncommercial and commercial purposes."
Check the sites for all these programs if you are interested in learning more about them.