If you have access to an IDE, why would anyone use a text editor?
hrabago: IDEs are big, slow, rigid. Text editors are lightweight and fast.  You'd have to weigh what you get from the IDE vs. what you're giving up.As for your other question, yes, there are ruby and python plugins for IntelliJ.  The python one seems new and immature.  The ruby one should be better.  They (Jetbrains) actually just came out with a standalone Ruby IDE as well.  I think it's meant for people not already using IntelliJ, because it wouldn't be worth paying for both products since the Ruby plugin works well enough.