Hello everybody,

I have a question if there are any services which allow to find a file by its hash in the web.

The original problem is the following: I have an image, but I do not know where it comes from. i wonder if it is possible to make "reverse-hash" lookup (i.e. find the web address by its md5sum or sha1). I tried in google and yahoo, but it seems they do not have such function

Thanks in advance,
Best regards,