The Linux Disk Usage Analyzer Baobab provides a visual layout of your files and file system usage.
Baobab is part of Gnome in GnomeUtils, so is included in most recent Linux distros.
On Debian / Ubuntu, install with:
$ sudo apt-get install baobab
Baobab provides options to scan a specific directory, your home directory, then entire file system, or even also a remote file system!
Here are some pics:
