I just spent the last hour "futzing" with eclipse to edit a large xml file that I was writing an XSL for. Eclipse would crash, and hard. I had lots of memory allocated to it (about 1gb).
Out of frustration, I fired up Microsoft Visual Studio, and copied and pasted my xml into the file, and IT WAS AUTOMATICALLY FORMATTED! Awesome. Even if I could get eclipse not to crash, it took a minute for it to format the xml.