BlueStack have launched a beta of their Android App Player for Windows. With the beta you can play thousands of Android apps on Windows. You browse from a collection of apps and then can download them and use them in Windows. It uses Amazon appstore, GetJar and 1Mobile Market for the app stores and searches through each of them, basically it looks like a Android emulator for Windows. You can sync BlueStack with an Android phone so it will sync apps, updates and photos from your phone.
I am going to give it a try on my Windows 8 test machine.