Found this crossing of Australia on bicycles by a 10 year old and his dad.
Follow Geoff and Dan at
www.danmallo.com as they pedal from Perth to Sydney 4000 km (2500 miles, sound more impressive in kilometres.)
I didn't even know about the Nullarbor when I was 10, let alone wanted to cycled across it.
Go Dan, GO Geoff.
cheers
Eddie