Yeah, I don't know that I'll even use these myself, but I figured I could at least help with the design if nothing else. I do quite a bit of vinyl work, and something like this is very simple and easy to do. I'll have to do a blog entry showing some of the things that I've done.
Having said that, I personally wouldn't care all that much if someone could really read it from a distance. I don't think I would care if someone approached my house, to end up reading it on the window they were able to break into and have them question the security of the home, and end up moving along. To me, the important thing would be that it's easily recognizable and understood at the door/windows where it's placed.
Personally, I've taken a different approach. While I certainly wouldn't want anyone to break into my home and have to deal with any damages. I don't necessarily want to advertise that I have an alarm system at all. That could result in having utilities cut and a quicker snatch and grab if said intruder has any expectations. I prefer the unsuspecting approach, where if someone were to open the door they hear the alarm sounding and have just realized they messed up and better take a run for it, because they have no idea what's coming next ;-) But then again, as I said in an earlier post... I'm not all that worried about someone breaking in with multiple police vehicles on my street.