How Do You Get Clean Water and How Much?

More or less a question of curiosity more than anything. Do you boil water or use tablets if you even bother with the process at all. I know there are those out there that don't worry about giardia and stuff like that. I know there are some new ways to get clean water like the Steripeen that uses light to kill any bacteria in the water as long as the water is clear.

I preferr to boil my water. It's safe and I don't have to worry about it not working or breaking really. I had considered getting a filter but up here in Alaska those aren't so great with all of the glacial melt I've heard. Too much maintenance for me right now. I've always got my stove and I can always build a fire if need be.

Also, since we're on the subject of water here, how much do you guys usually carry with you? I'm know there are quite a few variables here such as water avaliability on the trail, weather, days on the hike, elevation, etc.. I usually just fill up my 3 quart Camelback with a nalgene bottle on the side of my pack with water and that can last me a day, day and half if I want to stay well hydrated.

Usually where I go backpacking there are always water sources(creeks, ponds, etc.) so I've no idea how I would do in a desert climate. Although I can use the Iraq days as a guide, lol. Though those were a little extreme in the hear department. Nothing like drinking 5 litres of water on a 6 hour mission in 120 degree heat with gear on that raises the temp 10 degrees and sweating it all out.

There are probably more posts here about water than any other topic. Use the search engine to find the threads and posts.

There is a recent thread on the new MSR filter.

I filtered for about 15 years and thought it was great, then learned about ultralight backpacking; now I use tablets. (Chlorine ones have a lot less aftertaste than iodine.) No ill effects yet - knock on wood. I don't bother treating water that's going to get boiled for dinner. If the water seems too murky to drink before using tablets, it's not hard to use a bandana or something to filter it out first.

I do most of my backpacking in SE Alaska and around western Washington. Water has almost never been a problem to find, so I only carry 2 liters at a time. Don't know anything about desert climates. :\