These anime-related lists were created by the regulars of the Usenet newsgroup rec.arts.anime.misc, and compiled by me from their posts.
Links have been provided whenever a title has an Anime Primer entry.
This list, from January 2005, was in response to a newcomer to the group asking for shows similar to Sugar: A Little Snow Fairy - non-violent, cute, and appropriate for a 7-year-old girl. Additions to the list were made when it was re-posted in April 2006.
¹: For those of you who think Card Captor Sakura doesn't belong here, I provide a comment from Rose Prescott:
Way back when Censorship was a real issue, there was a great fuss about James Branch Cabell's Jurgen. But what it finally came down to was a judge noting that it was all very symbolic, and nobody could be corrupted by it - because you already had to know what it was about to understand what it was about. (I've read it. Lovely book, very wistful. For years, there were Cabell otaku. I was one.)
Sakura is a perfect example of this, from a different medium. If you're innocent, you think "how sweet, the way everybody likes each other". It's only if you've got a bit of mileage on your spiritual odometer that you begin noticing some of the details.
(With the comments that gave reservations about recommending them)
This list, from early-August 2005, came about as a reaction to yet another show with sexualized young-teen protagonists. Not all of the leading characters in the anime on this list are adults, but most of the leading characters in each anime are either adults or in their late teens - college-aged or older.