I've got a new PC (a prety good one, by the way)! I immediately transfered my files to it and deleted they from my old HD, just to find that one folder had been corrupted: my personal folder, the one that kept ALL my drawings and sprites (and music, games, etc. but those I can download again).
I've spent last night awake finding an good "undeleter" program and (sucessfully) trying to recover my files back from the dead.
From now on I swear that I will backup everything, I would have freaked out without my sprites: they-re my art, my form of expression, and I hadn't actually thought about how much they meant to me until now.

I will resume spriting as soon as I can organize my files back: I'm making a sheet of Samus Aran (from Metroid) in MLSS style [link] and I will try showing a WIP soon.