Negative 17 of 1
As of when I wrote this, Flickr seemed to have stalled out at -33 of 1.
Hey at least it's not Processing -4i + 2 of 7pi
I got something similar whilst transferring accounts from a cPanel-based server to my Plesk one using Plesk's Migration wizard. It said "Transferring domain -3 of 2". If I saved the screenshot somewhere, I'll post it one day.
I suggest using the new uploader.