[ame]http://www.youtube.com/watch?v=4HQ1WJ5ebu0[/ame]
This is by far the coolest theme that I have ever stumbled upon in the 4 years of my "iPhone'ing". Typophone 4 is free in Cydia and it will make your Lockscreen a lot easier to use, and give you a little more class. Typophone 4 changes your Lockscreen date and time to something a little more artsy. You are going to need a few things for this to work perfectly, don't worry, they all come from stock Cydia sources and they are all free (including Typophone 4):
1. SBSettings - Slide to the right on your status bar and hit respring after changing your wallpaper to the one you want.
2. Winterboard - Enable Typophone 4(also allows you to respring if you do not want to download SBSettings)
3. Lockscreen Clock Hide - Disables native iOS clock on lockscreen.
4. Typophone 4 - Lockscreen theme.
This theme works with 4.1 Jailbroken devices, I would recommend it to everyone with a Retina display (works on older devices as well).