A search for domains like mysite.com provides thousands of results on Stack Overflow and hundreds on Drupal Answers. I sampled some. Each and every one I checked was a post by someone ignorant about http://example.com, http://example.org and .example TLD, as defined in RFC 2606. Other "natural examples" domains are abused pretty much too.
My request is - disallow these:
- [one letter repeated].TLD
When they are detected, propose http://example.com or http://example.org. With old questions, use robot or find other way to edit them.
Even if SEO is not a problem, professional sites about Internet and associated technologies should not ignore RFC on such a large scale. Not to mention linking porn like about thousand links to xxx.com - I was already detected as one who visits "sites related to content forbidden here" by a firewall or two thanks to that.
I can assure you: you don't want to explain to your boss why are you searching for "adult content" in working hours, or agrotourism farm owner why that happens under his roof. Even WSODs are not nice. Now I think I have SE whitelisted, but anyway... Sadly, firewall was right, I did have xxx.com mentioned in my search results here and on Drupal Answers.
xxx.com. I've had an unpleasant experience.