The whole thing is the Scotland flag with the red bits from the English and Irish flags on top.
And a bit of a white border for the English bit.
( Edd: The Unfunny Try-Hard Edgelord, Tue 27 Nov 2007, 10:14, archived)

and the red diaganals are from Potato land.

( Damion International - now taking orders., Tue 27 Nov 2007, 10:18, archived)