Just saw this over at slick deals and picked it up.
Dead Island (PC) is on sale for $9.99 at new egg (free shipping/no tax). Not sure if this is just a one day deal or what exactly, so check this out asap if you've been wanting this. I believe this is the retail packaging, but you can likely register it through steam and download if that's your preference.
Here's a link to the deal directly: http://www.newegg.com/Product/Product.aspx?Item=N82E16832220034
Here's a link to where I found the deal on slickdeals: http://slickdeals.net/f/3861084-Dead-Island-PC-9-99-with-free-shipping