Re: Accurate Ads
One Time VM's come into play here which are naturally VPN'd out to foil their location sniffers.
The problem is it is very difficult to hide yourself from those that want to find you. Everyone has a routine, and even if you stop ads, and keep deleting your cookies (as I do) it is still difficult to hide. Think of the websites you use every day. It only takes a handful of those to either uniquely identify you, or put you in a very small set of people who do likewise.
If they have web log entries for your sites they can piece together that it's you. google-analytics.com is used by nearly everyone, and the jquery code you need for a website is often served from some cdn such as ajax.googleapis.com. There, they have you!
Hmm, your connections only ever occur during UK hours. You always read English language pages. You like to look at a lot of sports pages. It doesn't take much to narrow you down to a small set of people.