Developing this stuff is like having a lot of pockets, and putting notes in each pocket about a tool you need someday to make the whole thing work. Every day you try to take a note and replace it with an actual tool. Sooner or later you look around and every pocket has a tool, and you figure what the heck, let's start building the thing.
Joe Moreno got the "silo-safe" ball rolling with Adjix, preparing for his own demise, and being sure that our links would still work, even if his server went permanently kaput. It's possible to do this from Day One. That was one of the tools.
So I started working on the Minimal Blog Editor, all the time planning to use the tool to make it store your feeds where you want them, not necessarily in my space. Pretty important idea.
Today I got it working.
That's the prefs page in my.reallysimple.org where you tell it that you want it to publish the feeds into your own space on S3. It works.
PS: I bought a new domain today. There's a hint in the screen shot.