Adjective : an avid moviegoer. ,avid for pleasure; avid of power.    From Dictionary.com. 

He eyed it without favor, but with a sort of fierce avidness almost obsessional.    From Wordnik.com.  [People of the Dark]

Had they developed just a keyboard, my avidness for the iPad would have been a lot calmer because the huge issue for working on the iPhone was just, I'm a really good typist and I'm even a really good thumb typist, but there's a limit to how much you can do.    From Wordnik.com.  [PCWorld] Reference

GH Varley Board of Directors, with the assistance of their NSW Workcover Agent QBE Insurance's pre-ordained, network of corrupt rodents, have with avidness, squirreled themselves away behind closed boardroom doors and mind's to profit from the manipulation of New South Wales Occupation Health & Safety Legislation.    From Wordnik.com.  [Sydney Indymedia - Comments] Reference