Activities and the move to context-oriented desktops

It *is* useful if you have a big screen so can avoid maximising your app
all the time, or if you bind a key to windowshade your app (trivial with
any decent wm). Then you can have a bunch of per-app widgets (generally
folder widgets) giving things like graphical file management (useful? yes,
if, say, you're working on something with images in it: instnt
thumbnailer!) on a per-project basis.

One thing I'm not clear on (because I haven't looked) is how much of
plasmoid functionality you can bind to keys. (Next time I'm near a system
running X I'll have to check, but I'm on the wrong end of a modem right
now.)