Cylinder - Sexy homescreen icon animations
Galarm - Social alarm clock and reminders
Winterboard - Give your iPhone or iPod Touch a graphical overhaul!
Alarmy - World's most annoying alarm app
Lockinfo - You can find this app in Cydia - Tweaks.
Alarm Clock Xtreme - Alarm Clock Xtreme: Alarm, Stopwatch, Timer (Free) is the most popular alarm clock app created and published by AVG Labs for both iOS and Android devices.