From Art Knowledge News via geology.com:

…One of the largest known
Tyrannosaurus rex specimens ever discovered will be offered by international
auctioneers Bonhams & Butterfields on Saturday, October 3, 2009 during the
company’s first Natural History auction to be held at The Venetian ® in Las
Vegas. The auction will contain approximately 50 lots of
fossils with the centerpiece of the sale focusing on the expertly mounted female
T. rex, expected to bring millions of dollars. The rare 66-million year
old Tyrannosaurus skeleton – dubbed “Samson” – is arguably one of the three most
complete specimens to have been discovered…