Q. The Eames chair, the Aeron chair and the Barcelona chair: what do they have in common?

A. They all cost a fortune and are uncomfortable as heck to sit on.

I remain perplexed by people who buy chairs by reputation instead of comfort.

Nutty.

My Gymnic exercise ball [top] has been my working desk chair of choice since the early 90s and I have yet to meet its match.

Amazingly enough, it still costs only $26.95.

Using one of these balls for sitting is a whole different ballgame — as it were.

They require "active sitting" — that is, constant, unconscious movements of the back, torso, and legs to stay comfortably atop them; this is the best possible remedy for back pain and disc problems, as well as being an excellent prophylactic device against same.

In addition, venous stasis can't happen, since you are always moving just a trifle.

And, it's tremendous fun to bounce up and down while you work.

People will think you're nuts, fair enough — I know several attorneys who've tried and loved my chair but haven't put one in their offices because of its visual frivolity.

Too bad for them.

These balls were originally developed and perfected in Switzerland, then used for decades in physical therapy all over Europe before making their way to the U.S. about 20 years ago. Even so, they're still mostly an underground phenomenon here.

Bonus — I took my second chair out of my office and substituted a second ball-chair: instantly, the number of people stopping by to shmooze and hang out and waste some time dwindled to nearly zero.

Take it from this board-certified anesthesiologist: this is the way to go.

Helpful sizing hint: most adults will find the 65 cm size ideal.

It comes in bright royal blue: who could resist?

Once you try it, you'll understand why resistance is indeed futile.

Bonus: The ball comes with the lifetime ferrous-clad bookofjoe guarantee.

If for any reason you're not happy with yours, simply let me know and I'll cheerfully refund every penny you paid for it.

Wait a minute....

There may be a reason why this Internet stuff isn't working out very well financially for me.