I am sure a lot of you know about this, but I have only just found it and thought it was worth a share -
http://www.virante.com/seo-tools/pagerank-recovery-tool
I have found a nice couple of incoming links going to dead pages on there. It all helps.
Always really impressed by the tools on virante. Too many sites just regugitate the same (questionable) approaches just to pick up some seo tools links.
They do have the most illegible CAPTCHAs though.