I want to recommend the best Pad Thai in Boulder. I've visited every restaurant that offers pad thai in boulder (there's at least 8), and there are two that come out on top for me. The #1 pad thai in boulder is from Thai Avenue in the food court on the hill. Not only is it the cheapest ($7), but it's always hot and fresh and you can watch them make it right in front of you.
My second favorite is from May Wah in the plaza on the corner of Baseline and Broadway. It's only $8 for lunch and you get a huge portion. It's a little different than the P.T. from Thai Ave, because it's a darker, thicker sauce, but still very good for the price. I also really like the chicken they put in their PT because it's marinated or something, really tasty!
Ahoy Aloo or whatever it's called on Canyon and 28th is good, but it's way too expensive (I think $12 lunch) Get their Chef's Special noodle, or Srirachi Noodle instead.
Chez Thuy is the worst pad thai in boulder, don't even think about getting it. I've been dissapointed twice there because the noodles were so overcooked, it was just a pile of mush. They do however have the best Pho and lots of other great dishes, but that's for another thread topic...