The OLPC project has had some tough times http://radian.org/notebook/sic-transit-gloria-laptopi gets into some of that and some forays into other things.  The area about Qt/Trolltech supporting Windows as well as Linux is what prompted this post as well as the overall tone around there that ultimately software rarely doesn’t, and *SHOULD NOT* care about the kernel.  Hell it shouldn’t have to care about the UI much at all, that should be left up to the windowing environment.  You should be able to indicate hot keys and get the windowing UI to mostly just handle it.  And guess what?  That’s mostly how OS/X works.   Unfortunately it’s windowing API and system are only found on OS/X, as are the majority of it’s APIs.