I first tried to shake the coffee to see if I could make a mess, didn't work. When the mug is empty, the github logo becomes visible and you can click through to the github repo.

That's an illustration of the difficulties. I got the disk, video dvd and even drank the coffee but I initially thought the notebook was some sort of box for the video so didn't realise you could open it to read!

How do you open the notebook?

I can drag it around, no problem. The cursor also changes to a pointy hand when over notebook's right side, but clicking doesn't do anything. Nor does click-and-hold-then-dragging.