Icosahedron

An icosahedron in 238 bytes. This is all of it:

r = sqrt(3 / (1 + 2*sqrt(5)/5) - 1);
for (j = [0, 180]) rotate([0, j, 0])
for (i = [0:4]) rotate([0, 0, i * 360 / 5])
for (k = [0, 1]) rotate([0, -atan(r) - 2*k*atan(r/2), 0])
rotate([0, 0, 180*k]) cylinder(1, 0, r, $fn=3);