I don't think this is exactly breaking huge ground here, but it's a feature that I was sorely missing from UE - saw another post in here as well.
Problem: Taking an "ugly" XML document (no line breaks) and making it "pretty" by indenting and putting in proper line breaks, etc.
Solution: Set up a Tool in UltraEdit to use tidy.exe
1) Download the HTML Tidy program from here: http://tidy.sourceforge.net/
Make sure to get the command line version (win32, not 64-bit). The name of the zip should be tidy-exe.zip
2) Unzip and place the tidy.exe file in your Ultra Edit directory (or anywhere else for that matter).
3) In UE, go to Advanced > Tool Configuration. Enter the following information
a) Command line: c:\<somepath>\tidy.exe -xml -i -m %F
-XML tells it that it's an XML file you're delaing with
-i tells it to indent
-m tells it to modify the file in-place
%F is UE's placeholder for the currently-active file
Of course you can play around with tidy.exe and see if there are other/better options for your use.
b) Menu Item Name: XML Tidy
c) Command Output: Output to List Box. Everything else empty or unchecked.
d) Press the "Insert" button to save your changes to an external tool.
That's it. Grab an ugly XML file, go to Advanced > XML Tidy and if it worked you should get a "... has been changed by another application. Do you want to reload it?" message. Click yes and you should have a nicely indented XML file at your disposal.