Back in May, I found a TB that hadn't been logged as in the cache that I found it in, so I grabbed it to move it along. Turns out, last time it was logged was April 2012 in British Columbia (I live in Ontario). So I traveled with it a bit and now it's back in action.
Also, I lost one of my own TBs while longboarding to work one day, and a month later, it resurfaced in Tokyo, Japan. It's crazy how some things can turn around like that.
I have two missing TBs though, but they've only been missing for about a month so I'm not too worried right now.