I have been keeping a close eye on my system performance since getting my macbook with istatpro widget. Recently i have backed up about 3-5 dvds using mactheripper and toast. I noted the hard drive capacity remaining before and after each rip and burn and noticed that after i delete the folder in which the dvd was ripped on my hard drive, my capacity remaining doesnt return to the initial size. For example, after the last dvd, i went from 63.70gb free to 63.66. Are there other files being saved to my computer that im not deleting or what? Please help.