If you read Slashdot, you've no doubt seen this, but if not... Mark Russinovich's blog aired some of Sony's dirty laundry last week, when he outlined how one of their copy-protected CD's installs a kernel-mode rootkit on your machine without your knowledge.
His initial analysis is really interesting, as is his analysis of the "patch" and phone-home behaviour of the rootkit, and his follow-up to the counter-claims from the software's developers.
The ability to effect change by complaining on your personal blog depends on havign an audience, and having credibility. It's cool to see the effect these postings have had - Sony are scrambling to fix this and the press coverage means more people will be aware of CD copy-protection and copy-protection in general.
Update - Nov 9th: The next round from on Mark's blog is here, in which he slices and dices the uninstall process that SonyBMG makes you jump through.
Update - Nov 14th: Sony will no longer manufacture any CDs using this DRM technology, and is re-evaluating their DRM initiative. Microsoft's Anti-Spyware tool will include a signature to recognize the rootkit and allow it to be removed.