Strange, hidden folder in Applications folder?

Question

I was running low on disk space, so I ran Disk Inventory X and came across and hidden folder in my Applications folder called "private". I can't access it through spotlight or looking through the actual Applications folder, but there it is on Disk Inventory X, taking up almost 7GB. About 2 dozen sub folders with names like "vm" and "var" - inside are cache folders for different websites and big files named "sleepimage" and "swapfile0" - "swapfile5". Haven't run across this before. Anyone know what this is? Tell me I'm just being paranoid here.

Answer 1

drwxr-xr-x@ 6 root wheel 204 Sep 20 2008 private
It appears /private is in its original place, so the incidence of it under Applications would seem to be a copy.
That is has 7 GB within is a large amount of data and is unusual, but put that aside for a moment.
Just to check the system's ownership of it and also to make a comparison, issue these two commands, first one then the other and compare the results.
ls -al /private
ls -al /Applications/private
A duplicate would see identical results. I think you could delete the 'duplicate' one under Applications, and your computer should still function but doing a backup beforehand would be wise, if you have the facility to do so.
The only snag may be deleting the duplicate if it is owned by the system, otherwise known as root. I don't know if Directory X gives you the ability to delete stuff at that level.
Posting the output of those two commands back here will help in deciding how to get rid of it if you run into problems.