Help Billfred Outdo a Prankster and Win a Prize!

[Billfred]

Alright, here's the tale...

I live in a University residence hall. 200-something people, and I'm on the first floor. Right by the stairwell, so I'm a frequent victim of the ding-dong-dash. (More specifically, people bang on my door and run up the stairwell, thus evading their doom since I can't get to the door fast enough to see them.)

However, I see an opportunity to level the playing field. Over spring break, University Housing is installing peepholes in every door in the building. It doesn't seem too hard, IMHO, to use this newfound resource to catch the person(s) doing it. Problem is, I just don't know how to do it.

With that, I have the requirements:

• Through any method of the designer's choice, the device must be able to record an image of a person through the peephole while a banging is in progress.
  • "Black Boxes," which record the last X seconds of motion, are permissible, provided they record at least the prior 60 seconds.
• The device, once built, may not require any modification to the door, and it must be removable from the door without any marks or damage to the door. (This keeps Housing happy.)
• The device must be affordable, meaning it would cost me under, say, $50 in equipment.
  • I have the following equipment, which is fair game: a Pentium II computer running Windows ME (don't ask), a USB web cam, miscellaneous junk that would be found in a college student's room.
• Once installed, I must be able to still use the door.

What does the winning design get? Definitely a good rep click, probably a button if I see them, and perhaps some Krispy Kremes if we meet at a competition. (Delivered off-site, of course.)

I'll be very interested to see what the group comes up with.