I don't know how long it would take, but I really, really want a way to make Cyberduck (open-source FTP client; I use the Mac one) respond to global keyboard commands, so I could upload things to the current directory while I had them open or selected in Finder without clicking and dragging. I really want that a lot. Anyone who can make that happen for me wins my undying gratitude.
So, the London community is arranging a Hackday where some of us will get together and code. In order to ensure we work on the awesomest idea(s) possible, we decided to ask LessWrong to add to our list of candidates. So here is the question:
What could a few developers do in a day or less worth of coding that will be awesome? Also, as a way of checking calibration, you can give your estimate for how long such a thing would take to build.
Note: While we will take ideas and voting here into account, there is no guarantee that we will actually end up choosing one or more of them.