My fiance is a sports nut, well most importantly an AFL nut... He has been a Geelong supporter from birth and it consumes his life during footy season (and actually off season too - is that what they call it?).
He knows I tune out at anything AFL related, and so will never expect this.
For his bday in Feb I bought him cuff links with the Geelong colours to wear in his French cuff shirt on our wedding. He will NEVER suspect that in a million years. I think it will bring apart of who he is to his outfit, even if only small will mean alot to him.
Bought from Benjamin Cuff links, here (every cuff link you can think of!)