 The main things discussed here are not a concern...
but the subtle things are. First, a company that installs software on your computer, like an active X control, can find out much more about you. Don't ever allow active X controls to be installed unless you are certain you know the company, because when they are run, they have access to your computer information. Spyware is often disguised as an Active X Control.
Similarly, any executable that they want to run or download. Don't do it.
But EBAY doesn't do this. They use other means. Addressing Modee's question earlier, I think the reason that even though you deleted cookies and tried again, there was so much coincidental about your computer they allowed you to continue. Or, I have noticed, in some instances, that exiting the browser and going back in and suddenly it doesn't work anymore. Like the browser caches them.
The other thing they can use to a degree, although imperfect, are your computer settings. This is a vast amount of data available to any web site. OS you are running for example. Resolution of your screen. Among other stuff.
What would be interesting, Modee, is this.
1. Repeat what you did in your original test.
2. Now change IP Address and close your browser.
3. Log back in. Did they recognize your computer?
If not, it is likely a combination of IP Address and coincidental configuration information.
Obviously they are getting sneakier.
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