ClockAlone

Parkour? No problem! No one will make you fall, because you can make players invisible. Simple right click in air while holding watch is enought. Click again to see them.

Updated to CraftBukkit 1.7.2!

Permissions:
clockalone.bypass - They will still see you.
clockalone.use - Use the clock (default for all)

Crafting:
Craft your watch like vanilla one!

Installation:

1. Download ClockAlone.jar
   
2. Put it into plugins/
   
3. Run CraftBukkit
   
4. Done!
   

How to use (Polish)
http://www.youtube.com/watch?v=RZypXwZTtdU