A case in point is Match by Jos Muller for Quasar. You see a pendant version above. It is a square of polished aluminium in one of two sizes (12cm or 6cm) with a coloured strip of acrylic on one edge which surrounds a linear LED (8W or 3W). That's all.
It can be used singly, of course (maybe hanging over a bar with others, widely spaced, or over a display case) but, because it is small, it can also be used in groups:
The picture above can't really do full justice to how good such an arrangement can look (there are great examples in Quasar's showrooms in Giessen), but here's a view from a distance of a larger number...
There is a range of Match wall lights, single...
...plus single or double versions on a back plate:
The single ones can be composed to make crisp patterns across a wall:
By now, Quasar were on a roll! So there are table versions:
and even floor versions -- a single one or a group of three, as here:
All except the floor lights are available in the two sizes.
At this point, you are probably saying to yourself that that is all very well and good but wouldn't a round one be more conventional than this square shape? Well, Quasar are way ahead of you! Here's Can: