I saw a Nexus 5 concept by @TechyTee and knew I had to have the lock screen immediately......
So I went ahead and used a couple handy apps to create the sumbitch. First off, this is a Widgetlocker theme, however, the Zooper skins can (obviously) be used wherever.
I also threw together a handy installer app for the skins and the slider. Get it HERE
Need a dark wallpaper? Get one HERE
Use an image editor (Photoshop, GIMP, etc...) to personalize the widget. 225x225 pixels is a good size. ;)