Basically if you are a type that hits many programming languages this app is for you. If you have multiple websites that you manage then this app would be for you. They make many plugins for this suite that it is well worth it. Now before I started to use this I was a hugh fan of Adobe Dreamweaver . If anyone would try to tell me different I would tell them that they are nuts.
Now an app like Dreamweaver costs around $350.00 USD. Aptana is free but you can buy the professional version which gives you some more advance features. That would cost you $99.99 USD. I will give Aptana credit cause they do not cripple the free version like some others do. This app will run in Mac, Linux, and Windows. In the next day or two I am planning on making a tutorial on this app to give you a tour of it.