Chrome spray paint

I haven't ever used it, but my understanding (back when all things chrome took off) from mates who were into moding cars was that it is hard to do well. You'll need a black base layer to help give the shine it's reflection, and above all it needs to be done on a very even surface.

I think doing it effectively on a bike would be tough. Have a search on the internet, especially on car modification forums.

EDIT: here's some tips http://www.ehow.com/way_5374477_chrome-paint-tips.html

huge +1
tried it a few times (on audi wing mirrors lol), I was told you need a satin black paint underneath, in some area's it worked great, but mostly, it was aweful.

Kind of reminded me of cheaply galvanized 5bar gates (brickman = farmer in a previous life) where all the flakes of coated zinc are shiny/dull depending which angle they are viewed from.