Version 1:

Na na na na na na na na
Batman!
Racing down the motorway,
A lorry came the other way,
Flatman!

Version 2:

Na na na na na na na na BATMAAAN
Swingin' from an elastic band,
Fell into a pot of jam,
Along came Spiderman,
Thought he was a jelly man
And AAATE HIIIM....