Aquilifer, it would move relative to my car down the straight, and would appear to be at different distances when looked through front or side window, so not an artifact on the monitor. It was also only visible from the chicane to entry of turn 3, and would appear behind trees when looked at from the chicane.
My processor seems to be dying..maybe thats what caused it, never heard of it causing a glitch like that before though. When I shift-F4'd and ran Paint Shop Pro, then went back to LFS and shift-F4'd back, the object did disappear, maybe it'll be back the next time my system is toasting..
Didn't look like any object i've seen in LFS before, but it must be LFS related, because it wasn't permantantly visible.