I managed to port the Android L Calculator. Check it out!
As mentioned in the title, here's my port of the Android L Calculator: http://forum.xda-developers.com/google-nexus-5/themes-apps/app-android-l-calculator-t2802018/post53837712
I tested it on a Nexus 4 and Nexus 5, and it seemed to work great!
Here are some screenshots: