I tried this new feature from Google called "Image search" where you could search almost anything using an image. For example, if you have a low quality Alizee picture and would like one with higher quality, then you could upload it to search for similar pictures with higher quality. You also might be able to use it to find out more information about that picture (i.e. where, when it was taken, etc). It's still on its early stage, but I find it very interesting.
http://www.google.com/insidesearch/searchbyimage.html