Maybe you could just say "actually, it's spunk. YOUR MOTHERS SPUNK"
That would be brilliant.
( Lollylegs lite, Sat 3 May 2008, 1:17, archived)

or "this t-shirt used to be plain, before i visited your mother, now it's got this all over it"
Ahh I wish I had a shirt like that...endless possibilities.
( Lollylegs lite, Sat 3 May 2008, 1:19, archived)