Something very weird happened to me yesterday. I was viewing one movie with VLC player and suddenly an alert box appeared saying me "Your start-up disk is almost full". What? I had more than 8gb free, what is that?
Effectively, I had. Then I had just 400mb. 395, 380... Agghh! I just closed VLC and it continued doing that, so I thought: let's restart!
After restarting, fortunately no more space was consumed but, I still kept having just 300mb free. I presume VLC was storing too many frames in the cache or something (since it was the only program that I was using at that very moment) :D
I started looking at several folders where I thought that the temp files could be, but after finding some of them, and deleting old files, and taking the opportunity to delete old stuff I wasn't using, by the way, I still was with just 500 mb free.
If you know a better way to do this, just leave a comment :)