For a while they were a video artist's novelty, and going for several hundred dollars each on eBay.
See:
http://en.wikipedia.org/wiki/PXL-2000
"Also in Los Angeles, Pixelporn, a one-time all Pixelvision pornography festival was held in 1997"
Some still go for good money.
http://www.ebay.com/sch/sis.html?_nk...H_Sold=1&rt=nc
.