Compact Compass

I always need a handy and compact tool in my pencil case, whenever I need to make a mind map or Venn diagram, but I can't be bothered fiddling with a compass and setting it up to draw a single circle. However, I didn't find any with a good pivot design in the centre; they just relied on the user keeping it as still as possible, which could be difficult sometimes. They had a fixed centre instead of an active centre, so setting up one of those was more of a hassle than setting up a regular