I found that I regularly emailed myself notes and files for later processing, and they'd then get lost in the inbox. I wanted to be able to search my notes (and only my notes), as well as easily share them with one or several people.
Every other one of those services got me partway there but felt like they were lacking (no web search, burdensome to use, etc). Paste and forget until later - no more than 20 seconds to save something.
Notifications and device web apps are coming, too. Does that help?