I paid $20.00 for a bag from Bentley's here in Canada. It's withstood 5 years of service, even though it's only heavy duty canvas!
It was originally designed as a business bag, to hold a laptop and assorted odds and ends. There are all sorts of pockets in it. A large external pocket holds my stethescope and BP cuff. Another one holds batteries for my pager, stethescope and hearing aids. The large pocket on the left side holds my CPR mask and epi kit.
The outher main compartment (of which there are two) hold my paperwork and daily schedule (soon to add a laptop to that!!) There is a row of pen holders, which also hold my scissors. My thermometer goes in another small open compartment where I can grab it in a hurry. The other one holds frequently used odds and ends such as needles, connectors, a few gauze sponges, alcohol wipes, thermometer covers, etc, etc.
I can't believe my company is still giving out these itty bitty fanny packs to the new nurses!

Mine now holds my tidbits and course markers for when I do dog tracking!