ClippingMagic.com - Remove image backgrounds online. Make backgrounds transparent, white, etc. Edit, crop, rotate, fix colors, add shadows, all you need for great photos!
digiKam - Professional Photo Management with the Power of Open Source
Bg Eraser - Background Eraser on Mac and Windows.
XnView MP - XnView is a free software that allows you to view, resize and edit your images. It supports more than 500 different formats!
Hyper Headshots - Hyper Headshots is a cloud-based web app that allows you to convert photos into beautiful and professional headshots with ease.
Adobe Photoshop - Adobe Photoshop is a webtop application for editing images and photos online.