Lee Kum Kee Chili Oil
Lee Kum Kee chili oil is damn good stuff. I always try to keep a bottle of it handy in the house. I like this brand of chili oil a lot because there is something snappy and intense about the smell and taste of it. Use this as a dipping sauce, marinade or even mix it with noodles. One of my girlfriends actually uses this as a salad dressing. I stopped buying it for her when she started brushing her teeth with it.
I get mine at any Asian supermarket.