I kinda made up my own. I have a synthetic-leather one that folds up like a book and zips. The Z fastens to the right side and the left side has a holder for business cards and other misc items.
In order to keep the On button from being pressed, I used my wife\'s hot-glue gun to place a mid-sized dome-shaped drop close to where the left side would be hitting the On button. The glue goes on clear and dries to a smoky grey color. The glue remains soft enough that it does not scratch the cover of the Z. When I close or zip the cover, the dome of glue is against the Z case and does not allow the cover to push the button.
The other thing you\'ll want to do is start up the Voice Recorder and look in the options menu for the check-box to disable the start recorder with the calendar key. If you don\'t and your case presses on it, you\'ll be amazed at the conversations and office noise that you can pickup when you\'re not expecting it.
When the 5500\'s first came out, there was also a program that you could install that would get invoked when the Z was turned on. If you didn\'t tap on the screen within so many seconds, it would turn the Z back off again.