Recently got a BSOD on my PC without a reason (in Win8 it looks much funnier :)), after that I've notised that around 10gb on system partition space is missing. I've checked and cleaned memory dumps, temporary files and so on...but freed only 1gb of hard drive space...I've noticed that WinSxS folder is very big, but I don't remember how big it was before this accident and do not want to touch it right now. Any suggestions? Maybe story sounds familiar? Thanks.
Update. Restoring last backup worked like a charm, but still this situation makes no sense...Anyway I think case is closed, thanks everyone!