It's more of a repeller then a track the ball follows. When it gets close it will bounce back at the complementary angle to its approach to the track for a normal ball. I haven't tried it yet with an Anti grav or Android ball.

For most of the IO's except for maybe the first Google has given away more free stuff then the cost of the conference itself. A noticable group has went simply to get this swag. 2 years ago they gave out 2 phones. Last year they gave out a special edition Galaxy Tab, a 4g LTE Mifi, and a Chromebook to attendees, and certain sessions also gave out things, one was a PS phone and one was an Arduino. I think almost doubling the price to $900 from last years $550 (I believe) is more to attempt to drive these people out. I was there last year and you could tell who was only there for the swag as they sat in the back and left the sessions or keynotes for the swag desk as soon as things were announced.

cool

I used these back in 1993-1994 at the Pennsylvania Department of Transportation. They were replacing a paper system used to inspect bridges with an electronic system because 95% of the data never changed and they could save time only typing in the new Data. The system was pretty cool and I got to write most of the code on the laptops and field test it. They were made by Grid systems . They still make Pen based computers some can be dropped and some are waterproof. At one time they were owned by Tandy, who also owned Radio Shack.