You might remember that the old Volkswagen Beetle used the exhausts heat surplus to warm the inside of the car. It had an air cooled motor, so no liquid coolant to do the job. A sleeve was wrapped around the exhaust pipe and cold air from inside the car was circulated in the sleeve and back in the car. Our Canadian winters (and over generous use of calcium on the roads) soon rusted then perforated the whole contraption, permitting the mix of stale inside air with fresh exhaust gazes. Mmmmh!? Of course, on really cold days, you could also count on the optional gas heather, that used gas from the tank, and brought your gas mileage to a few miles per gallon (and also shortened your life drastically...).

Ahhhh! More people who refuse to "break in" book spines! When I took a speed reading class years ago, the first thing we learned was to crack the book open every 50 page or so BEFORE reading it, so it would stay flat on the reading surface for faster page turning and general comfort. Yes...my books look as they have been read...but shouldn't they? My books lie flat! The triangular part sould be made squarish...as a shelf.

The picture of the two side by side cube is also a good one for 3D illusion. If you look at it a bit cross-eyed (some practice necessary...) you will see the cube in 3D. It's usually done without colors but also works in this case because of the careful color choices.