What strikes me about this four-wheel innovation — and I believe that it is an innovation — is that it shows us that there is still room for invention in even the most ordinary things. That's is good news for us. Another example of how innovation is possible in even the simplest things is rolling luggage: do you realize how many years (centuries) it has taken to put wheels on a suitcase? I assume it's a matter of rising labor costs — when was the last time you saw a porter at a rail station? More here, here and here about history of rolling luggage.

![[book cover]](http://citycomfortsblog.typepad.com/cities/cc-cover-100w.jpg)
