Yeah I've always thought an API-first todo system could be very powerful. That said, I'm not sure if starting with an API is best way to get traction. You need a ton of traction (at least in a niche) to get websites to entertain the idea of integrating with your platform.
I'm not sure yet how you'd kickstart it. I can see existing players like Todoist and Trello expand their platforms over time to provide such functionality though.
I use nvALT (fork of Notational Velocity mentioned by @jillbinder) for my text notes. It's great and very fast. brettterpstra.com/projects/nv…
I occasionally use iCloud-synced Notes.app for things that I need on-the-go and synced immediately. (I also use Dropbox to sync my nvALT text files but I still haven't found an iOS app I like for it).
Design inspiration images/video I store in Pixave, although I don't use it a ton. www.littlehj.com
Other than that I don't store many random snippets.
@marcantoinefon report it to amrith. he will attack the spammer with his chocomel-infused stickerpacks
I tend to use lvh.me for subdomain testing so I can do something like wip.lvh.me which just forwards to localhost. ( coderwall.com/p/-neplg/use-lv… )
I also use the ghost Rubygem to manage my /etc/hosts file. github.com/bjeanes/ghost