I hate this trend that I'm sure advertisers just love of signing in to one account (like, HuffPo) by using another (facebook). I've last facebook since they're just another arm of Madison Avenue and the NSA. If a site is good enough to warrant my membership, I will just give them a unique username and a unique password (thank you, Lastpass) and register it with my throw away email address.
I'm considering creating a false ID for online use with fake name and other demographics and run it through a VPN exiting in Sweden instead of the US. Use it from a machine where I change the mac address daily and the browser is run in a virtual machine hosting a Linux distro.
