I delayed for two months (personal anxiety over authority figures, sigh), but finally dropped a copy of the To Touch the Stars CD that we did years ago on his chair. I also sent him an e-mail letting him know it was on his chair, why I'd put it there, and that he should not feel obligated to listen to it. ;-)
I did this, of course, on a weekend. Even though he had a enormously important internal presentation later that week, he still sent a thank-you note within a matter of hours.
To my surprise a few weeks later, this morning there was another thank-you letter from him -- personal, hand-written -- and hand-delivered by his admin to my office. He thanked me again for the CD, called it "inspiring", and said it was now on his Zune (for you non-MS folks, that's a sort of iPod).
For context, this guy has about 10,000 people reporting to him and a $17 billion annual business to manage. I think he's busier than, well, anyone I know other than perhaps Alisa.
Especially in that context, it was really inspiring to see that kind of courtesy displayed.