I have been thinking for quite a while about where to invest some time studying new stuff (new for me, at least). The reason is that in my opinion a programmer cannot afford to stop learning new things, because our world is changing too quickly. Of course I'm not saying that one should run after every single buzzword, but keeping the habit of learning is IMO very important in general, and vital for a programmer.
I was just about to buy an iMac with dual intel core, for both experimenting programming for a true multiprocessor and for looking at OSX; I stopped mainly for a quite stupid reason... apparently there's no way to get the video output of my Windows XP into the iMac screen, so my choices were either to find space for the iMac in addition to what's already on my desk (impossible) or to work on XP just using VNC (that's no life). Oh... and 1700 euros were sort of a stopper too :-)
So I went for a cheaper solution... I'll invest time on linux, and I mean on linux as my only desktop system at home. I installed a Debian distribution and so far I'm quite happy with it; I got my NVidia card working with hw acceleration under X, a nice desktop (KDE), all peripherals working (including the video capture) and even win32 quasi-emulation (I compiled a win32 app I'm working on using bcc55/wine!). CVS/SVN and dvd playing, r/w access to my XP partition, firefox, thunderbird, VLC... everything is ok or almost ok. I had to pay basically nothing (just the work of freeing my very old 16gb HD with win98, and the risk of seeing what happens when XP boots from a secondary IDE HD). Now I've just to look for a replacement of the few applications I use (e.g. chess software, ms works). I'll need of course to use XP every now and then, and the solution is now changing the boot device in the bios.
One keyboard, one screen, two worlds.