DotWhat.net – File Extension Information
http://dotwhat.net/

DotWhat.net is a site dedicated to providing you with detailed file extension information. This site is based on a huge database of file extension information, mainly (but not exclusive to) the Microsoft Windows, MAC OS X and Unix based operating systems. This has been added to World Wide Web Reference Subject Tracer™ Information Blog. This has been added to Script Resources Subject Tracer™ Information Blog. This has been added to the tools section of Research Resources Subject Tracer™ Information Blog.