What is a good app to see the detail of app "usage" on OS X?

[eseerc]

The "storage" section within About my Mac shows that I have a little over 60GB in "apps" that is counted toward the storage on my MacBook Air. When I look into the applications folder on my MBA, I barely have 20GB of apps in that folder. Is there an app that will better show what makes up the various items taking up storage on my MBA?

 

[Rob Phillips]

I use DaisyDisk.