I like mixing a little blob of Strobe Cream or Strobe Liquid from MAC into my foundation (MUFE HD) and buffing it into my skin with the 187 brush.. It's a pretty common trick.
Also, applying NARS Albatross Highlighter onto the tops of my cheeks and down my nose adds a nice glow (MAC Lightscapade is better if you can get your hands on it since it was LE!). Also, apply bronzer (NARS Laguna) on your temples, right under your cheekbones and lightly on your forehead and cheeks.