Question: All of the ones I can think of are specific products that have come to represent their kind. This is usually either because it is the first of its kind, as in a Xerox machine (the first office photocopier), or it arises from popularity, as in Sharpie or something like "Google that" (though I'd say that's a bit informal/debatable).

Other examples I can think of off the top of my head are:

* Kleenex
* Post-it

Answer: 
* Aqualung
* Aspirin
* Astroturf
* Band-aid
* Bubble wrap
* Butterscotch
* Cellophane
* Chapstick
* Coke (only in some regions)
* Crock pot
* Cuisinart
* Dumpster
* Dry ice
* Escalator
* Frisbee
* Jeep
* Jello
* Jetski
* Hacky sack
* Heroin
* Hoover (mainly in the UK)
* Kerosene
* Laundromat
* Linoleum
* Muzak
* Q-tip
* Tarmac
* Taser
* Thermos
* Trampoline
* Velcro
* Walkman
* Yo-yo
* Zipper
* iPod (I've seen many people use iPod to refer to any MP3 player)
* Xerox
* Zip-lock