A really cool "building toy" from the mid 80s made by Fisher Price. Basically you connected beams with knots (my own terminology except for knot (see below). I cannot remember if there were official names for the pieces) to make whatever you want. Other pieces available: wheels, little men, and a host of other decorative lego like objects.


Little (maybe 1/2" or so) blue cubes with small rectangle-type things sticking out on each side, allowing you to snap beams (see below) onto them.

           |    |
    ,------`    `------.
    |                  |
  ._|      .____.      |_.
  |        |    |        |
  |        |    |        |
  '-|      '----'      |-'
    |                  |
    |                  |
    '------|    |------'
           |    |

Light gray pieces meant to mate (snap together) with the knot. The most commonly found beams were rectangular, however, there were also a few other shapes including curved pieces.

front view

  |          |
  | |------| |
  | |      | |
  |_|      |_|


Planes that snap into place in the middle of beams with little tabs. If memory serves correctly they were mostly dark blue. Later on, Fisher Price made glow in the dark beams and plates.

a beam connected to a knot
                  ._| |_.
   |-------------||     |_
   |             ||      _|
   |_____________||_. ._|


my comments

The "manual" or whatever you want to call it came with this demo robot to build. I usually used the robot's feet and did the rest out of my crooked imagination. I have made hoards of robots, a telephone booth, and a myriad of bases. I was deeply saddened when I heard Fisher Price abandoned my favorite toy after only a few years. I used to look down on legos in favor of my Construx. update: I incorrectly remembered them as "Constructs". I also use the term beams instead of grays...It sounds better in my opinion. A google search will result in a bunch of neat "fan" sites often with pictures. You can find a good amount of Construx for sale on ebay. update: mkb told me the blue connector pieces are called "knots". another update - construx being spelled correctly was pointed out to me by another noder and I forgot his name..if it matters to you, /msg me again and i'll put your name on here, heh.