Here is the list of tools being used in an Agile environment as discussed in this forum. I have added some based on my previous experience as well.
(Updated on 8th Feb 2013)
Let me know if you are using any other tools, happy to add them here. Above picture is a screen shot from my excel and feel free to Google it around to get more details about each of them, or Drop me an email and happy to share more details about the same.