Here are some I prepared earlier...

To get the ball rolling, I have decided to upload some doodles I've done in the past. They weren't doing much anyway, just hanging around waiting to cause trouble, so this'll give 'em something to do for a while. All these are biro (black ballpoint pen) on paper, I think there are some napkin drawings in there too, napkins are particularly nice to draw on with ballpoint, particularly when you have a cold or are a bit sad.
I'd like to some day be able to pay for a meal by doing a quick doodle on a napkin and handing it to the waiter, (think Picasso used to do that), whatever about the money you'd save on eating out, it would just look really cool... won't be trying it any time soon though. Anyway, I digress, here are the doodles...