Here is my review of the first 720p h.264 HD Spy Pen. This covert camera records pretty decent footage, and is leaps and bounds ahead of the 1280x960 mjpeg 'HD' Spy Spy Pen that I reviewed a couple of years ago. The live video-out function might also result in this camera getting some use outside of its intended (and unlikely) spy pen purpose.
I believe that this pen is related to the 808 #18 camera from the fact that it is distributed by the same sellers on ebay. It is therefore likely that the firmware could be updated, and the small time stamp removed, although at the time of writing I cannot confirm this.
If you buy this pen and want to change the time, it uses the familiar technique of copying a text configuration file to the built in memory. You can dowload an example file here. All you need to do is edit the contents to show the correct time and date and then copy your updated file to the pen. The time is updated when the pen is next switched on.
I mentioned in the video that this was a difficult review to shoot because I kept accidentally pressing the on/record button in transit and filling the memory up with footage of the inside of my bag or pocket. Every time this happened, the day's shoot had to be abandoned so I could return home, attach the camera up to my computer and empty the card out. After this happened twice I ended up taping a protective cap over the pen to stop it happening again. This is the only time that I've had a problem like this with a camera, and it was caused by the fact that the camera only needs one brief tap for it to both switch-on and automatically start recording. The fact that the memory can't be removed or swapped out also contributes to the problem. There is also no way to tell if the camera is on or off by looking at it. I know that this is so that it can't be detected as a camera....but it also makes it very hard to use as well.
If you want to buy one, here are a few links to stores on ebay.