The Designer Emulation Kits (DEKs) from Mark McKenna are tiny tributes to famous lamp designs rendered in circuit board and LED, made to clip onto a standard 9-volt battery.
You can buy them online for $35 or pick them up at the MoMA store in New York.
Product Page [MMcKenna.com via Red Ferret]
I bought one of these and I’m sorry to say it was a waste of money. The parts didn’t fit together well and it ate a 9volt battery in a day. Utterly useless.