 Blocking Cookies Is Obvious...
except you can't log in to ebay with them blocked. Good idea to block them where you cannot use them. Perhaps work or someplace you never want to really log into EBAY, but may encounter a beacon.
The safest thing is to ensure you always have cleaned up your cookie trail before you log in to EBAY. Firefox has an ability to delete all your private data on every exit from the program. Explorer does not. It has a utility you can download called Cookie Monster that does the same thing, but not automatically. Explorer appears to operate better inside of EBAY though, so just be careful.
You can open your emails from EBAY and never hit a beacon unless you "allow" them. Don't. Block all images from EBAY. A quick examination of some, not all, EBAY messages clearly show beacons being used.
Beacons can also be placed on web sites. So, you could be browsing someplace you don't even know is related to EBAY and blam, you find a beacon. Blocking all images when browsing is kind of useless. So, you just have to make sure you delete all your cookies before you start. You can then even go to EBAYs site and they won't know who you are unless you actually log in.
An example of this kind of beacon is used consistently by advertisers like doubleclick or valueclick. You go to a website, and their beacons are there. As soon as you browse the sight, double click places a cookie on your system. Next time you hit a site that has a double click beacon, it finds your cookie. It makes a trail of where you have been. If you have logged into one of the sites, they even know who you are on every site you browse.
Ever wondered how come you go to one site and suddenly you have 30 cookies all from different marketers? If you haven't looked, watch the cookie count jump. When I come to askpins site, the only cookie added is aspkins. But when I go to BlockBuster or some other heavily marketed sites, I may get blasted with cookies.
I have not really tried this yet, but it would be a curious exercise to see if an EBAY cookie gets dropped on your system while browsing some related sites like Paypal.
Beacons are nasty, but a beacon without cookies is useless. They see a hit on an IP address, but have no idea who you are without a cookie. But once they start laying down cookies and you are not cleaning them up, it is only a matter of time before they identify you.
If you don't believe me that beacons exist, clean up your cookies and go to a few web sites and watch the cookies pile up. If you are brave enough, you can even allow an ebay message to display. If there was a beacon in there, when you are done with the message, you will have an EBAY cookie.
One more tidbit. Be careful responding to EBAY mail messages from buyers. Have you ever received such stupid questions in your mail that you just say to yourself, geesh, noone could be this dumb? For example, you say New everywhere in your listing, and they ask you is it new? Or questions that ask you to ship to timbuktu even after you specifically said you only ship the US? It is very possible that terse questions or form looking emails from an EBAY user are sent by EBAY.
If you have mail forwarded to a central email or respond from the wrong location the mail could identify you. I carelessly responded to one question from a forwarded email one day from an email address that was suspended, and bang, within minutes, I was suspended. I had been using that account on the same IP address for ages. EBAY caught me through that one email and linked me.
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