Imgur - Imgur is a free and simple image hosting service with image editing feature. Signup is optional.
Img.vision - Image hosting & video hosting for eCommerce sellers
Flickr - image and video hosting website
UploadHouse - Thumbnail and resize your photos and images
Photobucket - Photobucket offers image hosting and free photo and video sharing.
BeeIMG - BeeIMG is a simple, fast, easy image sharing solution created to fill up your image sharing needs.