The Wall Street Journal is running a series about online tracking and privacy protection. It looks like CCleaner does a pretty good job addressing many of the issues. However, I ran across a tracking term I never heard before: "beacons". Does CCleaner also have the ability to delete beacons? If not, it sounds like a fairly critical product enhancement.
According to Wikipedia, this is a server-side thing. Thus, CCleaner or other software can't do anything about it.