Most online video players have heavy code, which slows page load. My Plugin adds only picture of the player, after a user clicks on it, the player code is loaded.
It shows “shortened” links like bit.ly, goo.gl and other link shortering services.
Disqus is nice comments system, but realisation for wordpress does not support dofollow commentators links. There is a nice way to make disqus comments dofollow, without updating troubles.
Now my blog is dofollow. You can leave comments. After 3 comments your links become dofollow. I’m going to delete any link, that I suspect being spam.
Nginx is lightweight and quick http server. It is usually used as a caching proxy for apache or php-fastci. I prefer using php-fastcgi.
Here is howto, which allows nginx to use static pages, generated by WP Super Cache.