Imgur, Flickr, Photobucket, Pixieset, ImageShack, ShotsShare, Visual Society, ShootProof, Pixabay, SmugMug, Fotki, Zenfolio, Pixpa, PASS.us, Piikx.com, Imageshack Uploader, Picflow, SLiMG, PT Photo Editor, Fotonomy, Siftr, Spyne, MGER are some alternatives to SlickPic.