LDView for Mac OS X
An early version of LDView (1.0?) by Travis Cobbs has been ported to Mac OS X by Alex Rafits.
Download LDView 1.0 for Mac OS X
System requirements: It worked on a G4 1.25 GHz with Mac OS X 10.2.x. It didn't work on an iBook G3 466 (had Rage 128). So you probably need a video card better than a Rage 128.
LDView displays LDraw models using OpenGL. It has some pretty nifty display options.
There is a much newer version of LDView, but unfortunately it does not work on Mac OS X. It will compile, but because of QT bugs, it didn'tt work correctly. It appears there is a new version of QT for Mac OS X, so maybe we will look at recompiling LDView again.
Instructions
Place the Frameworks in /Library/Frameworks/, or ~/Library/Frameworks/ (that is /Users/yourname/Library/Frameworks/).
Put the LDView app where ever you like.
You need to download an ldraw folder. If you don't already have one, you can do this by opening the preferences and clicking "Install Ldraw folder" or visit the LDraw.org Macintosh getting started page.
When you have an ldraw folder, you need to tell LDView where it is in the LDView preferences.
LDView does not open a document when first launched. You must select "File" -> "Open" first.
When opening models, Alex told me that it does a ton of parsing so that it renders faster, so that is why it takes longer than other ldraw system tools to open the models.
There is a Help menu with more instructions there.
Known problems
If you have a Rage 128 video card, this app might not work for you.