FileProInfo - It's All About Files, Software, Online Tools - 100% Free
Thumbnails Cloud - The simplest API for generating file thumbnails
File-Extensions.org - Large computer file extension library with detailed explanation of each file type with links to download free or associated software programs.
Blog Cover - Cover image generator for your blog post
FileInfo.com - FileInfo is the central file extensions registry and contains a database of over 10,000 file types.
Screenshot Bin - Generate website screenshots and thumbnails at scale, right from your app. Screenshots as a service.