CodeCanyon - wpStickies v2.0.0 - The Premium Image Tagging Plugin | 2,11 MB
You can easily tag your images or you can create fancy tooltips on your images. It is compatible with most of the browsers and of course it is highly customizable! It supports also permission control and it is deeply integrated with WordPress. You can allow your users to create stickies but you can approve or reject them from a pending list.