It depends on how naughty you are.
I 'know someone' who has upgraded the bulbs to, erm, not exactly legal ones.
Standard headlight bulbs are 55w mine his are 100w! and he has set them up so that they don't blind people, but rather they cast a nice wide, long beam pattern on the ground.
They are also almost white, so along with his super-white LED sidelight bulbs, they give real good night time vision, and a much better look, too.
Both sets of bulbs, including postage, would set you back approx ?60.
Apparently.