Microwaving Styrofoam

I'm a college student and the only cooking implements I have are a microwave and my bathroom sink. About 50% of my diet consists of instant soup, the kind that comes in a little styrofoam cup.

The directions on the pack say to add boiling water and let it sit for a minute. In order to do this properly, I'd have to pour water in a cup (clean cups are hard to find here), put it in the microwave, get it out while it's still hot (which interrupts poker playing/talking/whatever), pour it in the thing, and then wait a minute.

This process sucks, so I've just been putting water directly in the thing, microwaving for 2 minutes, and letting it sit til whenever I decide to actually eat it. This system is just about perfect for me.

But, my friends have been telling me that microwaving styrofoam is a bad idea, so I decided to switch to the sucky method. As a result, I haven't eaten much in the last few days.

What's the consensus on microwaving styrofoam? If its bad, anyone have a simpler process?