I’ve started using FetchNotes as my todo-list/reminder/note-taking app, and I really like its simplicity - I think it appeals to my plain-text side, while also syncing across all of my devices (okay fine just my phone and whatever computer I’m using, but still :D). The web interface is pretty straightforward and is decidedly focused on the notes, if only because there are so few features available to distract you, and there’s also an iOS app and an Android app.
What I really have liked is the Android FetchNotes app. To add a new note, just open up the app, swipe right to left, and start typing. Your tags show up automatically so you can add the appropriate tags with a few presses and you’re done just like that. It’s pretty sweet, you can search by multiple tags at once and such, so there’s not really much need to keep things organized other than tagging things. And, I love tagging things, so that makes me happy.
I’m hoping more people pick it up so I can try out the @mentioning thing they’ve got going on :D