The 2003 birthday of a good friend of mine was coming up soon and I wanted to give him a memorable present. I bought him Steven Hawking’s “Brief History of Time” but I wanted the present to be more than just a book. I came up with a plan: an office-wide quest in which he had to find his own present. I scattered 7-8 clues around the entire office floor, one leading to the other: on the ceiling, in the toilet, behind the furniture... I started the clock and left him to explore for 10 minutes. I was certain he would have fun in this discovery process. I watched him look for clues with excitement all around the office. He finally made it to his own room, only to find the book taped to the bottom of his desk.
The last note stuck to the ceiling above his desk could be seen up there for many years thereafter.