I put three new computer books that I had in duplicate on the desk of a guy who I knew was interested in the subject (with a note explaining the gift).
He works mainly in a different location so I didn't see him for several weeks (during which time the books disappeared), but I did expect to get a thank you note by e-mail.
Did I ? Of course not.
I was then there when he by chance was in the same location. I left the subject of the books until the late afternoon to give him the chance to thank me for them. Nothing. Even when I finally mentioned them towards the end of the day, all I got was a confirmation that he had them. No thanks.
The next time I had a book copy to give away I of course decided that someone else would get it. Again someone for whom the book would be useful. So this time I asked this new guy first if he'd like a signed copy of "Real World Computing SharePoint 2007" (which is what this one was) and he said he would. I sent it by internal post with a personal (and nice) dedication.
Did I get a "Thank You" message by E-mail? Of course not.
If I ever come across him, will he thank me then ? I doubt it.
P.S. Two and a half weeks later I got a thank you e-mail (for the single book). Maybe he's been on holiday ...