One of the things I've been doing is to take a very close look at Adobe's DNG camera profiles. This has included writing dcpTool, which can compile/decompile/edit/process DNG camera profiles, as well taking a look at what Adobe build into their supplied profiles. This led to my work on understanding "hue twists", which I talk about extensively on my blog.
One of things published there are various visualizations of how Adobe's profiles actually impact on colors. However, what's posted on my blog are static images - to get a better understanding of what's going on, you really need to look at the visualization live. So I'm providing them here, in the form of gcx files that Apple's "Grapher" program (supplied on every Mac) can open.
There are two files. Both have data on the profiles from a Canon 5DII, plotted for eight of the most critical Gretag Macbeth color patches (blue, green, red, yellow, magenta, cyan, light skin, dark skin). The only difference between them is organization; the "profiles" file is organized such you can easily select on a profile by profile basis, and the "colors" file such that you can easily select by color.
This zip file has both gcx files in it.