Google has registered more than 520 domain names, according to ProNet Advertising's Neil Patel. (Whether all of these names actually belong to Google is up for debate.) Regardless, given the tit-for-tat nature of the Microsoft-Google relationship, it's interesting to ponder which of the potential products represented by these names could be on Microsoft's radar screen, as well. Might there be a plutomicrosoft, a Microsoft zipdash, or pornmicrosoft.com in the works? (Thanks to Microsoft blogger Volker Will for the link to ProNet.)