I cannot remember the exact date of my sighting, but i believe it was in the summer of 2005. i was traveling eastbound from sunrise blvd on white rock rd late at night heading to folsom when i noticed a triangular set of white lights following me. i decided to stop and when i did, it stopped too. it was maybe 500-800 ft high and maybe an eighth of mile to possibly a quarter of a mile behind me. it was dark, but i could still see that it was a black triangular craft. i would guess its size to be 30-60ft. or so, corner to corner. it was silent; i heard no noise from it. i got back into my vehicle and started driving slowly with my head out my window watching it. it began to follow me as i started driving, so i stopped again and it again stopped. i got a bit scared at that point and took off at normal speed limit and i watched it as it followed me for about another mile or so before it changed its path and i lost sight of it. white rock rd borders aerojet and lockheed martin has a sight in aerojet, so i assumed maybe lockheed martin had some experimental aircraft going on there or something.