[Joel]

I'm not sure where the idea or notion that Adobe products can be run on two computers simultaneously came from, but it's never been the case in my experience, and according to Adobe's End User Agreement FAQ it's still not the case:

If you own, or are the primary user of, a single-user or volume license Adobe branded or Macromedia branded product that is installed on a computer at work, you can also install and use the software on one secondary computer of the same platform at home or on a portable computer. However, you may not run the software simultaneously on both the primary and secondary computers.