The reason that RubyMine makes you more productive is that it lets you see many things that you have to remember or guess at when working at the command line. So not free, but if you are serious about Ruby programming not excessive.

If you want to upgrade after the first year you have to pay a smaller amount. You also get one year's worth of updates and a licence to use the version you have for ever. For educational use and open source projects the product is free. After the 30 days you have to register and this costs 89 euros for a personal license, 26 euros for a student license or 179 euros for a commercial licence.

You can get a 30-day free trial from the JetBrain's website. RubyMine from JetBrains is the obvious choice as it is currently being rapidly developed. Since then I have been looking for a replacement IDE with as good support and as important a future. Until recently you could use NetBeans to develop Ruby projects but Ruby support was discontinued in Version 7. The main reason for this is that Ruby doesn't have a standard development environment. Many Ruby programmers swear by this or that editor, I'm not going to name names for either programmer or editor. If you have never used an IDE to program, you may not know what you are missing. RubyMine is a full Ruby IDE that makes it easy to create and develop complex projects. If you are still using EMACs or some other text editor to build Ruby applications, you need to consider that there are better ways to work.

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