Disappearing hard drive space

[Diatribe]

Since I have started converting my movies to an AppleTV-friendly format using Handbrake and MetaX and even though I do all the encoding on my external drive, my hard drive space on my primary drive has been slowly disappearing from 9GB to 250MB. I searched for invisible files bigger than 500MB but didn't find anything. It is pretty weird.
Anyone know what to do or where to look? Is there some freeware alternative for Whatsize to check what is eating up my space?

I am kind of at a loss here so any help is appreciated.

 

[Diatribe]

Ok so I checked with OmniDiskSweeper and it finds 169GB of data but when I check with Disk Utility it says 179GB used (with 0kb swap file used).

So where the hell are those 10GB?

 

[gothamm]

Thats the case with me too. But its when i download torrents. For instance, i downloaded a 25 gb High Def Torrent and the Mac HD showed it as 25 gb less, even though i was 1% through my download. I guess the mac assumes you are going to fill that space, before it has actually been downloaded.

 

[videogirl]

Look in imovie trash

I used OmniDiskSweeper and found my 26 missing gigs in the imovie trash! Emptied it, and voila--back to normal!

 

[Diatribe]

Thanks for the help all. Where I did find it in the end was a 12GB Spotlight index file Deleted that and it all went back to normal.