Fufme

From Opendildonics.org

While their website hasn't been updated since 1999, the people at FUFME, Inc. promised to deliver a product that was "the most complete remote sex solution for the Internet and corporate intranet".

The idea was that you had GenitalDrive Model M (male) on one computer and a Model F (female) on another. Actions performed on one GenitalDrive would be transmitted to the other.

Based on the detailed specifications and FAQ pages, they must have developed functioning prototypes before closing their operations. That, or it was all an elaborate hoax.

If you were on the Internet in the 1990's, you most likely have heard of this product, so even as a hoax it deserves an honorable mention.