Mou.app1 minute to read
I'm that kind of guy that is always taking and making notes about everything I have on my head… so I started using Mou since it helps me to "code" my notes. This makes my life easier when I need to share it using some nice formatting of my mental notes.
Now with mountain lion you can also use the Notes app (that comes built in), but for me that is more like shopping list :)
Go ahead and try Mou, you'll be pleased.