This idea is at least a decade old. A simple tool to jot down brief notes, which I can use from multiple computers. The key feature is incremental search, i.e. entering a couple of characters and seeing the list of hits trim down as I type. No categories, no hierarchies, no keywords. A time-stamp would be nice.

I've got tons of uses for this: storing ideas, remembering URLs, tracking To-do's, and (with proper protection) saving passwords and account info. I'd like to dump my entire chaotic brain in it (for personal use only).

On the Mac, there are several applications which can sort of do this. NoteTaker, MacJournal, OmniOutliner, and VoodooPad come to mind. On the web, there are wiki's and and bookmarks. The Backpack website has a Mac OS X Dashboard widget, a great combo. Will Duquette's
Notebook also comes close: incr search and portable. There are lots of ways to do this - it's not rocket science.

But all of the above are single-machine!

On a PDA it would be moot, since those are so easy to carry everywhere, but there's no quick way to enter even limited amounts of text in them.
Is it too much to ask to have a solution which talks to some server, is portable, and can work in disconnected mode as well? All it takes is Tcl/Tk and perhaps Tequila + Metakit. I'm even willing to forego Tk and use the command line, as long as a rendered version in HTML is easy to automatically maintain (for that N770 thing...).
Let's call it
SyncPad. Simple idea, simple project, I wish someone would do it.