A YouTuber called The Q decided to make "invisible" wheels for his bicycle, by using (d'oh!) Plexiglas. While this is of course a terrible idea--aside from the added weight, Plexi doesn't deal with stress very well--it was actually fun to watch him make it:
Enter a caption (optional)
You'll note that he's only riding the bike on smooth, paved bicycle paths. How many curbs do you reckon a Plexi wheel would survive before cracking?