I found some veggies that will work. There aren't many individual serving, steamed vegetable options, but there is one that should work. I can take a package to work and heat it in the microwave.
My boss (a competitive bodybuilder) eats asparagus and snow peas which he puts into a microwaveable container with a little bit of water and pops into the microwave for a minute or so. So that's an option too.
Way back when, I used to do broccoli and cauliflower that way.