It was killing me the last few months that I was constantly running out of space on my hard drive. More even since I got my 11″ MacBook Air. So I asked if there was anything “smarter” than the built in Mac OS X that would tell me only when the drive was *really* full. There was nothing, so I made it. It’s now on the Mac App Store and you can have more info at http://diskalarm.com. It’s only 4 bucks and it might save your life one day.