http://en.wikipedia.org/wiki/List_of_generic_and_genericized_trademarks
List of former trademarks that have become generic terms
Main article: Genericized trademark
The following list contains marks which were originally legally protected trademarks, but which have subsequently lost legal protection as trademarks by becoming the common name of the relevant product or service, as used both by the consuming public and commercial competitors. Some marks retain trademark protection in certain countries despite being declared generic in others.
Aspirin
Still a Bayer trademark name for acetylsalicylic acid in about 80 countries, including Canada and many countries in Europe, but declared generic in the U.S.
Catseye
Originally a trademark for a specific type of retroreflective road safety installation, now a generic term.
Cellophane
Still a registered trademark of Innovia Films Ltd in Europe and many other jurisdictions. Originally a trademark of DuPont.
Dry ice
Trademarked by the Dry Ice Corporation of America in 1925.
E-mail
claimed by CompuServe in a 1983 Byte Magazine ad
Escalator
Originally a trademark of Otis Elevator Company.
Freeware
Trademarked in the early 1980s by Andrew Fluegelman, but the trademark status was abandoned following Fluegelman's disappearance and presumed death.
Heroin
Trademarked by Friedrich Bayer & Co in 1898.
Hoover
This is a trademarked product from the Hoover Company, North Canton, Ohio. Its popularity, mainly in Ireland and the United Kingdom, led to vacuum cleaners being referred to as Hoovers, and the act of using the vacuum cleaner as 'hoovering'.
Kerosene
First used around 1852.
Lanolin
Trademarked as the term for a preparation of sheep fat and water.
Laundromat
coin laundry shop.
Linoleum
Floor covering, originally coined by Frederick Walton in 1864, and ruled as generic following a lawsuit for trademark infringement in 1878; probably the first product name to become a generic term.
Mimeograph
Originally trademarked by Albert Dick.
Netbook
Originally used to describe Psion's netBook, trademark was legally cancelled in 2009, following a trademark cancellation case.
Petrol
Carless, Capel and Leonard invented the trade name "Petrol" for refined petroleum spirit.
Pilates exercise system
United States trademark formally canceled by court in 2000.
Primal Therapy
A psychotherapy. Registered by Arthur Janov in 1970. Cancelled in 1978.
Thermos
Originally a Thermos GmbH trademark name for a vacuum flask; declared generic in the U.S. in 1963.
Touch-tone
Dual tone multi-frequency telephone signaling; AT&T states "formerly a trademark of AT&T".
Trampoline
Originally trademarked by George Nissen for the generic "rebound tumbler."
Videotape
Originally trademarked by Ampex Corporation, an early manufacturer of audio and video tape recorders.
Webster's Dictionary
The publishers with the strongest link to the original are Merriam-Webster, but they have a trademark only on "Merriam-Webster", and other dictionaries are legally published as "Webster's Dictionary".
Yo-Yo
Still a Papa's Toy Co. Ltd. trademark name for a spinning toy in Canada, but declared generic in the U.S. in 1965.
ZIP code
Originally registered as a servicemark but has since expired.
Zipper
Originally a trademark of B.F. Goodrich.