Lunchtime doodle 01

I finally managed to scan the drawings from my nearly finished new moleskine and I thought the best is to publish them one-by-one. I have made all of these in my lunchbreaks at work to refresh my brain and eyes a bit. The medium is mechanical pencil on paper of standard moleskine sketchbook (somewhere between a5 and a6, dont know the exact size), time is between 15-20 mins each.
Here is the first piece...