This $2 bicentennial chip from the short-lived Gary's Casino at Tahoe (which I "borrowed" from an eBay scan a couple of years ago) usually sells for upwards of $3,000, and since my daughter probably will be getting married in the next couple of years , I don't figure to own it any time soon. Much of my money is already accounted for.
Of the chips in my collection, this one from the Ta-Neva-Ho is probably the rarest. I also have the $1 small key but am still looking for the $5, which probably makes that No.2 on my Holy Grail list.