Here's a concept that those of you who enjoy putting flashy rims on your car won't like. Goodyear's "Eagle 360" concept tire is completely spherical, precluding you from showing off LED-riddled spinners as you cruise the boulevard.
These spherical wheels would work via mag-lev (duh)...
Enter a caption (optional) Enter a caption (optional)
... and the company has some interesting ideas for how they would evacuate water and eliminate the need for steering linkages. Take a look and see what you think:
Sure, they occupy far more volume than a conventional tire and pose significant technical challenges, but don't be a negative Nellie. Instead let's investigate the possibilities. What I'd really like to see is a provision for the wheels to be hollow and with some type of access hatch. That way you could fill one wheel with dirty laundry, some water and detergent, and by the time you arrive at your destination, boom, clean clothes!
You could also insert peeled avocadoes, limes and some type of pestle in another wheel to create a delicious guacamole as you drive.
The third wheel could be used for smoothies.
As for the fourth wheel, the obvious thing to do is fill it with a large Elide Fire Ball.