I purchased three catalogs and inherited hundreds of .net domains. I never set out to own them, they were just part of the catalogs which I cherry picked for the domains I wanted. I made sure to insist on the registrar login credentials when I purchased the catalogs because the last thing I ever wanted to do was renew the domains. This way I have control and can sell them if I get any inquiries.
Well.... Zero, Nadda, Zip, Zilch
Not one inquiry on the domains so I have steadily been giving the domains away. I did not want them to end up on the GoDaddy expiry auction so I gave a ton of them away to whoever would renew them. I found a community in India that was receptive and the count has steadily declined. I refused to do a push because I wanted to make sure the domains actually got renewed which will keep them out of expiry at least another year.
So I figure I will be completely .net free by the end of the year, if I never see another .net again it will be too soon.