the usual gimmiky gadgets like Golf, football and car gift sets, jazzy socks, funny mugs, his favourite drink like a litre of whisky or vodka or a cd or dvd.
~get him a ticket or something to a event you can share with him or activity, like roller rink or something. let him know you appreciate him and love him with your actions, not gifts
~make him a home made movie of you and the family all parents love this kind of thing
~get a card instead or take him out for lunch.