If you ever find yourself stuck for a little plastic container to stick something in - meths, milk powder, a tipple or whatever then have a look here.

http://www.shcweb.co.uk/eshop/

All kinds of little plastic bags, pots, bottles and tubes ... prices seem very fair too.

Tesco 250ml apple juice bottles work well as a lightweight hip flask alternative, just throw the apple juice out and rinse well first