Check out the RADIUS iPhone5 Case for iPhone 5 and iPhone 5s from REIGN23. It was originally and successfully funded through Kickstarter, and I think it's a study in minimalist design intended to protect the corners of your iPhone. It's made of T6061 Aluminum (an alloy with magnesium and silicon) and it's assembled with stainless steel screws. Better yet, it weighs just 5 grams—for those of us in the States, that's 0.20 ounces. It comes in Red & Slate/Black, Gold, Natural/Silver, or Slate/Black, and it's priced at US$69.99. I think it looks sexy as heck, and I might even review it.
Check It Out: The Mimimalist Aluminum RADIUS iPhone 5/5s Case