I recently found, not in a pen store but in an outdoors
gear store, a small Fisher ball point pen. Bought it
because its small size (100 mm capped) and weight (6 g),
in order to put it in a small utilities pack for hiking
and the like.
It can be had in different colours.
Whether it does all the things it's supposed to do I don't know, but it sure is better at writing on difficult surfaces than other ball points I have (and it writes rather well on regular ones too).
It's not perfect, as it's really too small to hold comfortable and it seems like it's not taking refills. (Although it doesn't cost a whole lot more than just a cartridge.) But it's certainly good enough that I'm thinking of getting one of their larger pens -- or at least see if one of their refills fits one of the ball points I may already have. (I think I have some, somewhere...)
Fisher Space Pen's web site.