This is the second time I went to that coffee shop in Riau street, Bandung. (I won't name the place, since it might be considered advertising.) As usual, I brought a book (usually a couple of books) with me. The place was nice and cozy. I wen straight to the middle room, turned right to a room which has three nice sofa-like chairs. I ordered a hot latte, slouched and started to read my book. This was just perfect. And then, it happened again. I just couldn't continue reading. My imagination ran wild. This time I was thinking about writing a book on the art of programming. Or, a book on the real life of programmers. I am teaching a course on programming this term. Actually, the first class is going to be this coming Tuesday. I just want to teach the real thing, not just the theory. Okay, I will do that. I tried to cotinue reading. Again, I just couldn't do it. Now, I was thinking about something else. I was thinking about (advanced) physics, about Fermi-Pasta-Ulam problem.