Philesight is described as 'tool to browse your filesystem and see where the diskspace is being used at a glance. Philesight is implemented as a simple command line program that generates PNG files; a wrapper CGI script is supplied to allow navigating through the filesystem' and is an app in the OS & Utilities category. There are six alternatives to Philesight for a variety of platforms, including Windows, Linux, Mac, BSD and KDE. The best alternative is WinDirStat, which is both free and Open Source. Other great apps like Philesight are Baobab Disk Usage Analyzer (Free, Open Source), K4DirStat (Free, Open Source), DiskSavvy (Freemium) and Disk Analyzer Pro - Disk space management software (Paid).
Baobab Disk Usage Analyzer is a graphical application to analyse disk usage in any Gnome environment. Disk Usage Analyzer can easily scan device volumes or a specific user-requested directory branch (local or remote).
K4DirStat, fork of KDirStat , is a small utility program that sums up disk usage for directory trees, very much like the Unix 'du' command. It displays the disk space used up by a directory tree, both numerically and graphically.