I finally found the culprit the other day. Every 5 minutes, my laptop would flash the 'start up disk is full' warning and it would piss me off so bad that I wanted to throw Lionel (my laptop) out the window. Not really, but you get how I feel. I uninstalled my Adobe Photoshop CS5 hoping that it would free at least a GB or two. It didn't. My last resort was... are you read for it?.... Google. Of course. Google.
I saw this forum that gave a list of suggestions on freeing up disk space, including emptying the cache, uninstalling unnecessary softwares, deleting massive files. What I will be telling you is the one that worked best. It involves downloading a freeware called OmniDiskSweeper. You can download it for free here.
It basically sweeps your whole drive and it shows you which folders or files occupy the most space.
The forum I was in mentioned something about Macs saving recovered messages, which is known to take up a lot of disk space. The photo above doesn't show it anymore, but under MAIL, there used to be a folder called recovered messages. While cleaning my laptop the other day, it showed me that an estimate of 440 GB was used up by these. Upon opening the folder, I noticed THOUSANDS of files with an email extension. When I opened a few of them, I noticed that they were messages (with attachments) that were not sent out because of a) exceeding file size or b) no internet connection. I think of them as drafts of my drafts. I don't remember sending out THOUSANDS of emails with attachments but apparently, MAIL stores multiple copies of them. I deleted about five thousand "recovered messages" and was able to instantly free up over 400 GB of disk space.
As soon as I was able to free up space, I installed Adobe Photoshop CS6, which is why I now have a new banner.
Next time your laptop tells you that you have no more disk space, use OmniDiskSweeper to locate those unwanted buggers.
