I have a Macbook 2.16 C2D and I recently upgraded from 1gb of ram to 4gb. I boot up after installing the ram and i notice that my free hard drive space went from 84 to 81 gb. I still can't figure out where it went.
perfectly normal, when you put your mac to sleep it dumps the entire contents of the ram onto a file on your hard drive because you upgraded your ram the size of this file increased from 1gb to 4gb