Hey,
I have a platypus bladder in my crank-tank hydration pack, and am looking to replace it with a better style (i.e. that has a zip-top, rather than just an opening at the bottom). They're so expensive--i priced them at $25-30. Anyone have any secret cheap brand/trick?

rs
http://www.crazyguyonabike.com/journal/RaiSue2006