At work, I find myself with time (but not the ability or system to log in).
Check out Logmein.com. It's remote desktop but it actually allows you to play. It takes a while to get used to the laggyness and you can't exactly run a box army but you can do menial stuff like farm SLS's or v1 charm upgrades.
The best part is it works through a website over https so most web-blocking software won't block it.
Keep in mind after a month or so, it will try to trick you into paying for a pro version but you don't have to just scroll to the bottom of the page and there's a "continue without buying" link.
