Screenshot Bin - Generate website screenshots and thumbnails at scale, right from your app. Screenshots as a service.
Passion Hacks - 170 Free isometric illustrations available as PNG & SVG files.
Ui Thumbnail Generator - A simple way to generate thumbnail. For docs and demos.
Isometrica - 3D illustration constructor with 380+ isometric objects
FilePreviews - Thumbnails and metadata for almost any kind of file
Craftwork - A collection of User Interface resources made by Craftwork