Pro tip: if you download a photo that's from Flickr, and it has its original filename (e.g. "19175458082_73cd17a06d_o.png") then just take the first string of numbers, before the underscore (e.g. "19175458082") and add it to the end of this:
Code:
You are not allowed to view this content until you register.
Voila. Now you've got the original URL for that picture (and of course the URL for the associated account.
Try it out, using my example, and you'll find this account.