Do you have those rolled-up coin stacks where u live ?
During my "autonomous" times living in a, say, non-rented appartment, I`d make a stack of german 2c-coins about as high as my fist.
Then put tape around it really firmly and put it in your pocket.
No one sees it when u clench it in your fist on its way out for business.
As the physics say, E = 1/2 * M * V² , this triples the mass of your fist - and at least in germany, the thing itself is perfectly legal.
Have fun.