Triangle UFO with erratic movement early, slow approach, multi-colored lights to constant white lights.

As I was getting ready for work, I saw way off in the distance a light in a trailer park. It changed colors, so I thought it was an ambulance or police car. I'm guessing that the trailer park was about a mile away. The street light at night is pretty much all you can see of it otherwise.
 I was concerned because I knew some of the people there, one in particular I commuted to work with each day.
 But the light lifted off the ground, and so I thought it was a helicopter. But it then moved erratically, and I mean something crazy. I've seen helicopters lift off several times, but this was wild. And the range of colors wasn't typical from what I've seen.
 (At this point, I woke up my parents and we all watched it approach.)  It moved slowly, eventually coming our way, passing close to our house. That's when we got a good look at it. It was no helicopter. By this time, it's movement was straight and smooth. It seemed like it was flying much lower than the majority of planes I'd see in the sky.
 Just before it got to our house, it's lights changed to a constant, steady white. No blinking or any other colors. I could see the outline exactly. It didn't look at all like a stealth bomber. It was a perfect triangle with three lights on the underside, one near each angle. No sound, and it was moving really slow. I've seen helicopters move faster. If it was as high as the regular planes in the sky I would see (about those speeds), then it had to be pretty big. I later saw a news report of people describing the same kind of craft, and the pictures they showed were exactly like what we saw.
 I am a student, without any special qualifications other than artist (excellent with visual skills); my father is a military veteran; my mother is a housewife.
 SUPPLEMENTARY: The image at http://en.wikipedia.org/wiki/Black_triangle_(UFO) is the closest. The descriptions I read on various sites about these black triangles match what we saw.
 The following video I found at Youtube is exactly what I recall: http://youtube.com/watch?v=qpGc8w5Wu0Y
Witness indicates that the date of the sighting is approximate.  PD