Description : Aptana is a robust, JavaScript-focused IDE for building dynamic web applications.

Based on the HOWTO found at http://www.ubuntuforums.org/showthread.php?t=315444.
Credit : 23meg.
Changes : Corrected a couple of typos.

1. Download the installer from http://www.aptana.com.

2. Install the dependencies
sudo apt-get install libswt3.1-gtk-java mozilla

3. Navigate to the directory where you downloaded the installer in the terminal and do the following
cp Aptana_IDE_Setup.bin Aptana_IDE_Setup.bin.bak

cat Aptana_IDE_Setup.bin.bak | \sed "s/export LD_ASSUME_KERNEL/#xport LD_ASSUME_KERNEL/" > \Aptana_IDE_Setup.bin



4. Launch the installer and follow the instructions
./Aptana_IDE_Setup.bin

5. Use the following script to launch Aptana. This is assuming you've installed it to your ~/Aptana folder.
#! /bin/bash
export MOZILLA_FIVE_HOME=/usr/lib/mozilla
~/Aptana/aptana


Save the script. Call it "aptana", make it executable and run it. You can also drop it into your bin folder.

Note : I am not affiliated with the Aptana project. I just happened to use it some time back, and liked it.

Oh and there is no PHP support at the moment but it's coming soon. However, since Aptana is based on Eclipse, PHP-related plugins (such as PHPIDE and PHPEclipse) can always be added on.

Reading the site it seems that any platform that supports Eclipse (such as Fedora with GCJ in my case) can install this as an eclipse plugin. That might be worth investigating for an easier install