I've been using the free SimpleNote and Notational Velocity combo for a long time. It's indispensable BUT the interface is as basic as you get which makes visual organizing nearly impossible. Tagging is the only real way to organize. I see RealMac has now launched a version of it's Clear to-do app for the Mac which syncs with the iOS version via iCloud. It looks like it might be better at visual organization but at $9 for Mac + iOS version it is $9 better than the free SimpleNote and Notational Velocity? I don't mind spending $9. I do mind wasting it.