lightweight XML viewer can handle large files?

There are plenty of “heavyweight” tools such as XmlSpy, which are good for prodding around in xml docs - but often (very often in some cases!) you just want to quickly open and browse an xml doc, and have it pretty printed. Possibly with some basic search functionality (textual is probably fine).

I usually use a browser such as IE of Firefox for this, but they tend to break down for larger file sizes (I’m often opening files in the 10s of MBs or more).

firstobject’s 605k download lightweight native Windows free XML editor opens a 50MB file in 1.3 seconds and provides text editing, search, syntax-colored printing, plus tree view and additional XML features including formatting and full-blown CMarkup scripting built in. You can reformat an entire 50MB XML document to a different indentation (takes 3 seconds on a nothing special 2.3GHz/2GB machine).