a thicker tire is about the only thing i would recommend. as you get familiar with your commute and riding in general you'll know the sp[ots here there is glass and get a sharper awareness for picking it out on the road (so you can avoid it).
one good piece of advice i heard once is if your already on the glass don't bother turning, as the friction of the turn on the road/rubber/glass may cause the glass to go right into the rubber... if your on the glass and it's too late to go around the safest path (and the one least likely to cause a flat) is straight through.
some would recommend a tire liner. i say save your money on tire liners and just buy a nice tire.
i have found the thickest most puncture resistant tires to be touring tires (i am guessing you roll 700c wheels). my current favorite are continental top touring 2000's; good things are also said often about specialized aramdillo tires though i haven't tried these yet.