I am probably one of the few collectors of Sony’s Palm PDAs (which are not really rare). However, now I got also the rarest model of this series: the VZ90!
This last Sony PDA model was sold in 2004 in Japan only and had an OLED screen (actually it was the first PDA with an OLED screen). Back in the day it costed (list price) 95k Yen (about 780 Euro, or $830). Mine even works, horaay!
Rare & Old Computers 