Dokany
User mode file system for Windows
Dokany is the fork of Dokan, a user mode file system library that lets you easily and safely develop new file systems on the Windows OS.
When creating new file systems on Windows, you need to develop a device driver that works in the kernel mode on Windows-- a difficult task without technical Windows Kernel knowledge. Dokany makes it easy. It enables you to create these file systems without device drivers, and is completely free to download.