LMAO.... well you give something that's not of monetary value to him.
I'm thinking a Vacation from work. A break to some where foreign, if you can afford it. If not raise the money.
Careful with the L2 gift! Many successful men have honed their reputations over the course of their careers and would take offense to anyone that endangers it. If you're bound and determined to do it make sure it's done discretely and most definitely in a private location. If not, just watch his eyes (as he scans the room in fear of one of his business associates catching sight an dlosing faith in him) and jaw (whic he'll grind while contemplating how he's going to have your head for disrespecting him like that) for the answer to your question.
LOL Well, he isn't too discrete about that stuff. Very non-conforming. He would do it in back area of a restaurant semi out of view I am sure. I know he has upstairs at some dance clubs.
The original answer used to be for the guy who had everything, "Penicillin!". My solution is to get the person something that they might want, but would never buy themselves. Scotch beyond the legal age of a girlfriend is always welcome if they partake.