A good practice for software developer is to provide a test suite while developing a software. When developing for Linux, it's also a good practice to compile the software and run the test suite on many distributions like Debian, Ubuntu, Fedora, ArchLinux, Centos, Slackware and for both i386 and x86_64.
Usually, softwares are compiled and tested on only one distribution because setting up the right environment is long and painful. Most of the time root privileges are also required to setup such environment.
In this article and the following one, I will show that using PRoot, such testing is quite handy and can be done by any users.