Apple Newton Messagepad 2000
This is a Newton 2000 which has been upgraded to 2100 specification. For now, I'll send you to the Wikipedia entry on the Newton for more information.
This exhibit kindly donated (as an early Christmas present!) by the lovely Saffie
Already, I have got it doing wireless web browsing (of a sort) with a Netgear PCMCIA card, and being a (somewhat unreliable) web server. The Newton user community appears to be still thriving - there is even an app to sync it to iCal and Address Book under OS X.
Copyright 2008 Arthur Bullard.