One solid, three orthogonal shadows. Type a line per axis, rotate each in its own plane, and the trip-let is carved so every face reads.
The cover of Hofstadter's Gödel, Escher, Bach shows two wooden "trip-lets": blocks carved so their shadows spell G, E, B from three perpendicular directions.
The solid is built the honest way — the intersection of three prisms, each your text extruded straight through the object along one axis. A voxel is kept only where all three silhouettes agree, so the shadow it throws down each axis is exactly (at most) the line you typed. The real trip-lets needed the letters turned relative to each other to line up — that's the per-axis rotation slider.
The box is lit from inside: three axis lights graze the walls and a froxel volumetric — the occupancy grid uploaded as a 3D texture and raymarched — fills it with haze the solid carves shadow-shafts through. Turn on prisms to see the three extrusions before they're intersected; drag object size to shrink the trip-let inside the box.
Long or thin strings can lose pixels where the three can't all agree — that's the trip-let problem itself. Bolder / shorter / rotated reads best, and underline adds a rule that reconnects a word's separate strokes.
Or switch the material to dichroic: instead of one opaque solid, three directional prisms that go opaque only when you look along their axis and clear off it — so each face casts its whole line with no intersection loss. It's the "opaque one way, transparent the other" trick; snap to a View to read each plane dead-on.