I had Capsela as a kid!
I had Construx as well!
Friends and I occasionally reminisce about that special kind of joy we felt as kids, a kind of "pure" joy, that came from playing with various toy favorites. Despite many of us being fans of "grown up" toys like electronics, gadgets, etc, no matter the price tag or technological advancement, I don't think they're able to match that joy we felt as kids.
That of course is of little help in tracking down a Capsela set (or something similar), but I enjoyed the brief trip down memory lane.