In 'things I noticed but that wikipedia noticed first'...
Celestial Globes! Really cool! They draw all the stars in the sky, so you can learn the constellations! Except... You always look at a globe from the outside. And you always look at the celestial sphere (in as much as it exists) from the inside. So celestial globe makers have a fundamental dilemma - put the stars in the right place on the globe, and have all the constellations look backwards, or flip the entirity of the heavens inside out, so the constellations look right, but the more you think about it the more confusing it gets. Oddly, we don't seem to have converged on a standard - here's a 'each constellation looks right, so the globe must be wrong' one, and here's a 'stars in the right place so everything looks backwards' one.
If you like constellations, you could do a lot worse than the Digital Gene Constellation app, which is basically just a jigsaw where you can amuse yourself putting the stars in the sky until your sky has all the stars in it, but is gently pleasing, and taught me enough about constellations to get to the point where I went 'hold on a minute, that celstial globe must be wrong, surely?'
Also, we live in an age where you can put armillary sphere into Amazon and get lots of hits. Maybe capitalism isn't all bad.