A wobbling chair is probably the last thing you'd want to rest your body on, but if you're actually looking for a more engaging and dynamic experience, this almost spherical seat is probably something you'd want to try out.
Designing a chair that rocks in all directions isn't easy, even after you get the idea to use a concave base. You have to make sure you don't completely tip over to any side, which is what a lip or ridge around the base is for.
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