Backgroundifier - Turn oddly-sized images into beautiful desktop backgrounds
Gumlet - Gumlet is an end-to-end video streaming and image delivery platform
FreshBackMac - Fresh backgrounds for your Mac from multiple sources
Splashify - Beautiful desktop wallpapers for Mac and Windows
Resizing.app - Image resizing has never been so simple with free online resizing.app. Convert, optimize, resize images with ease and for absolutely free.
Shapy - Shapes & Images with CSS Gradients