I posted this on my twitter a couple weeks ago, but it's just so fn awesome, I figured it was worth posting here, too. If you're into noise makers, Mynoise.net is the most professionally compiled, high quality, diverse collection I have ever found. It also has a meditation room & animate option for each sound group, so you're not listening to the exact same thing. Be sure to do the calibration before listening. I donated within a day of listening, and I can be a stingy fuck. I really like the tonal drones, like the singing bowls -- it's very rare to find long, quality recordings of singing bowls that don't have some random frog sound thrown in. But nothing is stopping you from listening to frogs if that's your thing.
Oh yeah, they are all tuned to the same key so that they can be layered seamlessly.