I've got a 4 year old (I think) 17" macbook pro. The 80gb drive is almost full. I ran a disc utility and it said that the file count was off (by a small number, I think 5). I have noticed some performance problems, but nothing major. I have a 500gb WD back up drive that I'm using with Time Machine. I was just told that once TM uses this drive, I can't use it for anything else. That is, I was hoping to partition the external in some way and shifting my iTunes library to it to free up space on the internal. Is this not possible? Also, I understand that if I do move my iTunes library to an external, and try to go wireless from the external, to the mac, to airport express, I will notice a downgrade in both speed and quality. Is that true? Is my best solution to just put a new, larger drive in the laptop? I really only use the computer for the Internet, word processing and iTunes, so I don't think I need a new one. Thanks.