Tim Ong made some really nice ones.  They bolt onto the landing gear legs.  I'm using those.  So far they look great in my garage).  No flight reports yet.
 
I also want a light on when the gear is up.  I will use a Whelen light in the leading edge of the wing, mounted as in a Piper Malibu.  I think the Whelen part number is A775.  I have not yet made the housing and plexiglass lens, but I have sat in the cockpit with the wings attached and marked out a section of outboard leading edge which is not visible from the cockpit.  That is where the light will go.  It is intended for other people to see me, not for me to see the ground.

- Rob Wolf