A lamp made out of three Hella fog lamps ('Hella 1NL 008 090-821' to be exact).
The lamps are mounted upside down and are adjusted to light the ceiling but not the wall. They are nearly parallel to the ground but still only light the upper part. So you can see the exit point of the light but it doesn't dazzle.
The 12V transformator is contained in an Ikea Blanda Blank metal bowl - perfect fit.
A learning: Do not use speaker cable for anything that gets hot! I had this mounted 3 month ago, but the isolation of the speaker cabling melted and shorted. Thankfully I was in the room and could switch it of before everything went to hell.
Downsides: Gets horribly hot, draws just under 300W, really expensive (around 150€ in parts)