I've owned what I consider to be a "premium" domain for several years (since 1999 I think), and I've always told myself I'm going to do something with it but I never have and probably will never find the time.
Without saying what it is, it's a dictionary word prefaced by the letter "e". No hyphens, no numbers, just a good authoritative domain that I've received some five-figure offers for over the years.
When you look at all of the "domains for sale" websites, they seem to be filled with a bunch of clutter, multi-hyphenated URLS, foreign TLD's, etc. And of course they all want you to spend extra money on their promotion services so you can separate yourself from the junk domains they know fill their sites.
So where should I list this thing? Someone WILL want this domain when they see that it's for sale, but given the selection available on most of the domain aftermarket sites, I can't imagine any real serious buyers are going there with any frequency.