Stops abuse of your site's XML-RPC by simply removing some methods used by attackers. While you can use the rest of XML-RPC methods.

Keeps WordPress from sending pings to your own site.

Prevent pingback, XML-RPC and denial of service DDOS attacks by disabling the XML-RPC pingback functionality.

Secure your site's XML-RPC by removing some methods, while you can still use XML-RPC.

This plugin disables the WordPress XMLRPC pingback ping.

Enable conversation across the web.

Stops a WordPress blog from pinging itself with pingbacks

Prevents trackbacks and pingbacks from showing up as comments on posts.

Automatically close Comments, Pingbacks and Trackbacks. Manage and delete revisions.

Easily customize WordPress notification emails.

One step process to remove pingbacks and trackbacks and leave only real user opinions in your posts comments.

SMu DoFollow has many DoFollow Options (Manual or Automatism) and included URL Validator (Manual, WP-Cron or Cronjob).

Shows Pingbacks and Trackbacks above Disqus comments.

Manually add a Pingback to a post or page.

Add the option for a pingback notification to go to an email other than the site admin email.

Scans post for links, checks if they are pingeable and sends pingbacks with results returned, improves chances of successful pings!

Grabs related links from Google Blog Search, inserts a link to them into your post and gives them a pingback.

Follow Self Pings

Pingcrawl adds a "Possibly related posts" capability by querying Google Blog Search for post tags and pinging the results.

Kramer will add inbound links to a post on your weblog as pingbacks by checking Technorati and by monitoring incoming referrers.