Here's a link to the Schwenk Collection which I found on PCGS Collectors Universe World Currency discussion board. Many of these single examples have values that exceed the value of my entire collection (no surprise really).
He also adds what he actually paid for each note & has links to many gold & rare US coins. Worth a look if you want an ultimate note (or coin) to add to your collection. Its also a nice reference site for the big budget collector. I don't collect US large size notes but hey, “it's free to dream!”