Well of course your love and support, but that is an ongoing gift. I am guessing you mean for christmas... Well that depends a lot on him. You should know him if you are dating him, make it something that you know that he would like. Not something you would like for him. Listen to him when he talks, what does he talk about the most, what can you give him that is representative. Hope that points you in the right direction.
I have always believed that the best gift a girl can give her guy is oral love.
Is sex a good gift