Firefly started out as an online music recommendation system-- you'd rate albums and artists on a scale of 1 to 7, and Firefly would compare your tastes in music with those of the rest of the Firefly community, and then recommend artists and albums you might like based on the ratings of people with tastes similar to yours. This process is known as collaborative filtering, and it can be a very powerful personalization technology.

Soon Firefly applied the technology to movies, and then to books, in partnership with Barnes and Noble. In time, Firefly transformed itself from a cool online tool and community to a software development company, licensing its technology to 3rd parties. Shown here is Firefly's redesigned corporate site, along with the Firefly Passport, a "remote control" for accessing the Firefly Network, the sites that employed Firefly's technology.