Impossible tech

If you know any really hard tech/glitch, explain it here and I will make a challenge (or a track) about it (reverse drift doesn't count).

If a challenge says "without going backwards, by going backwards" it has a really hard tech: press the accelerate button for 3 frames, turnaround, press the backwards button for 3 frames, turnaround and continue until you finish the lap/you reach the zone.