A lot of the Scouts are using Camelbacks or other Hydration bladders these day, heck..so am I. These are great tools for maintaining hydration while in the outdoors.
Simple to use and they hold a lot of water, having the bite valve to suck on instead of opening a water bottle, the bottom line is the Scouts drink.
Maintaining a Bladder is a little different than cleaning your water bottle. And you need to keep your Camelback or bladder clean to avoid getting sick.
Here is a good little video from one of my favorite links Backpacker Mag. (online).
Check this out to see ways to keep your Hydration bladder clean.
First of which is you will tend to drink more. This is a good thing.
They are easy to fill and they hold a lot of water.
They are easy to clean, but you need to clean them often.
In a lot of cases, you can pump water directly from a Purifier to the bladder.
Most Backpacks on the market today (I know that all Kelty packs) have compartments for your bladder and access holes to run your hose through.
Again, the big plus is that you will tend to drink more water.
Hydration systems can run the spectrum when it comes to price. You can pick up a bladder, hose and bite valve pretty cheap, and you can spend a lot… either way, the intent to stay hydrated.
Check out this gear review on Hydration systems. It is real good and shows you the price ranges also.
Campmor.com also has some good deals on hydration systems. They have pretty much every brand. You can check it out here.