SeatSale: License to Sit.

Download a Seating License to retract the seat's content-guard spikes

Steve Mann, 2001 Feb. 7th

Here is the Internet Chair with magnetic stripe card reader and spikes that retract when a seating license is downloaded from a license server in response to input from the card reader incoroprated into the chair. The license server is in the 19 inch relay rack behind the Internet Chair.

The text on the scrolling LED sign mounted to the back of the chair reads:

The opening was Wednesday Feb. 7th, at the San Francisco Art Institute (SFAI, 800 Chestnut St.), organized by Independent Curators International (ICI) of New York, and curated by Steve Dietz of (Walker Art Center) of Minneapolis. SeatSale was also exhibited at various other museums and galleries, such as Austin Museum of Art, Oklahoma City Museum of Art, etc..

Across from the internet chair (pictured at left) is a VGA television display on a TV stand (pictured at right), which displays the following message:

Swipe credit card or government issued
photo ID card to download a FREE Seating

Your card is for identification
purposes only. The seating is FREE!!!

By swiping your card, you agree to be
bound by our Terms and Conditions.

Your swipe indicates your agreement to
these Terms and Conditions of use.

If you do not agree to our Terms and
Conditions, remain standing and do not
swipe your card through the card reader!

When a credit card or ID card is swiped, the following displays:
Thank you for agreeing to our Terms and
Conditions of use.
(spikes retract)
Enjoy Quality of Seating Services (TM)
Middleware and QoS Provisioning.
(a short movie plays)

After some time (e.g. after the movie has finished) a bright flashing animated version of the following is displayed:

then the following message is displayed while an extremely loud bank of 60 Hz warning buzzers is sounded throughout the exhibit space:

Your Seating License will expire in 4 seconds
Please swipe your credit card or
contact the SeatWorks to renew your license
WARNING: Your Seating License will
expire in 3 seconds!
Please get off the chair!
contact the SeatWorks to renew your license.

License Expired
(spikes unretract)
Here is the background poster installed behind exhibit:

which provides the philosophical background such as the Uniform Secure Ecommerce Accounting Transactions Act (UseatA), including some real world examples of seat licenses.

The poster is located directly behind the seat and relay rack housing the license server and licence manager, as shown below:

Here's a nice composite image of SeatSale and the poster:

You can also download a high resolution version of the above.

Here's a nice composite image of the poster and patent:

You can also download a high resolution version of the above.

See the patent:

Here is how the seat appears from a user's point of view, showing how the spikes retract when a credit card is used to download a FREE seating license:

Watch a video of SeatSale taken February 2001

You can download an mpeg movie of the seat from a user's point of view (approx. 20 megabytes), or you can download a closeup mpeg movie of a license being downloaded to the seat (approx. 2 megabytes). Another similar closeup movie is also available here (approx. 4 megabytes).

Here's a video still from the SeatSale surveillance cameras at SFAI:

Here are a few video stills from the SeatSale surveillance cameras at Austin Museum of Art (

You can help by keeping a watchful eye on our infrared security cameras to help us prevent theft of Seating Services (TM), and to prevent the smuggling of contraband (pillows, boards, and other tools of license circumvention), into the museum space. This site is a mirror of the live video. The video is also archived. See a day in the life of a seat-for-license. (Longer movie: weekend seatsale.)

SeatSale chair being manufactured in the basement of the Mann residence.SeatSale chair construction
Installation instructions for seatsale
Link to San Francisco Art Institute site curated by Steve Dietz through Independent Curators International (ICI) of New York. (There is also a local copy of the curator's statement here.)
archive of setup pictures from the site.

The New Deconomy:
DECONomics and the moneyless society

Sight License

See a 1998 exhibit (the opening date was June 1, which corresponded with my Keynote Address at the Virtual Reality conference in Rio de Janeiro) which also used a magnetic stripe card reader.

Here is a list of clients who were the first to download free seating licenses during the opening of the exhibit. (Credit card numbers, driver's license numbers, etc., have been replaced by minus sign "dashes".)

someone posted seatsale to slashdot which generated some interesting discussion.
Excerpt from SF Gate, San Francisco Chronicle, 2001/03/01
Scholarly article on the philosophy underlying the License to Sit: Free Source as Free Thought: Architecting Free Standards First Monday, volume 5, number 1 (January 2000), URL:
There was an article on SeatSale in the New York Times, which led to a radio interview that same day, on CNET.

Here is the cnet radio interview (encoded using oggenc; play using ogg123), but it's a huge file, almost 8 megabytes, because no time to sox down the original (even larger, almost 80 megabytes) wav file to mono, and since it's a phone interview, it really doesn't need 41k samples/sec.

Reviews of SeatSale

comments and reviews
link to main site
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EXISTech ( site

What does a solid oak chair have to do with wearable computing?
(This issue is addressed toward the end of the book.)
An interesting article about spikes: Franz Kafka In the Penal Colony (1919)