The iSmell from Digiscents, now sadly yet predictably bankrupt. An unfortunate name for a strange product, bringing the promise of "smellivision" to life. Except it died.
Imagine hitting a webpage and not being hit with a bad looped background midi song, but a (bad?) background smell. Say, tuna fish. The iSmell was designed to bring to reality virtual odour. It had a palette of 256 composite chemicals that smell designers could use to build simulated olfactory experiences. A great enhancement to any webfiend's peripheral collection.
One wonders what porn sites would do.
A related device is on the market from Telewest Broadband called the "Scent Dome."