I'm afraid that even after working at a grocery store for three years, the best I've got in American money is a 00858686, but I am particularly proud of my 2 Russian 1909 5 ruble notes with consecutive serial numbers that I was able to put together. The first (YA-117) I bought from a dealer friend of mine who saw that I had interests in Russian currency, and I later found it's brother (YA-118) on Ebay, so I picked it up!
~AJ