Apps That Do Not Sync via the Cloud

A useful-sounding idea from Shawn Blanc for what would be close to my ideal task manager:

And my next wish? A cloud-based service like Instapaper, but for to-do items. I want it to be available in apps like Tweetie, Reeder, and more, so when I click on “Do Later” it sends the link or item of note into a running to-do list that syncs with Things, of course.