I only discovered NYX Cosmetics a couple of years ago; can you believe that? I read that their lipsticks are a cult favorite--and very similar to MAC, but a LOT more affordable. NYX Cosmetics can be found at Ulta. I've read their lip creams are quite nice too!
Another one of NYX's more popular items are the eyeshadows. Many women have compared these eyeshadows to MAC because they are very pigmented.
I just purchased my first NYX eyeshadow in "Silk". It is a soft champagne color. I figured I would try it since Ulta was having a bogo sale. This is a great shade to use as a base or highlighter for so many eyeshadows that I currently own.