mitcho (Michael Yoshitaka Erlewine)

Sometimes you have a need for having links to external URLs show up interspersed among your own pages or posts. This plugin lets you easily create such “redirecting” posts or pages by simply setting a custom field.
Usage: Add the custom field with label “redirect” to any post or page. Enter the redirect target URL as the value of that custom field. Now all links on your site to that post or page will be replaced with that redirect URL! If you try to visit the permalink URL for that page, it will redirect the user to that redirect URL too.
This plugin actually also works fine to redirect a URL to another URL on the same site as well.
Placeholders: New in version 0.9: the strings <code>%home%</code> and <code>%site%</code> in URLs are replaced by the WordPress home URL and site URLs, respectively.
Development of this plugin was supported by the <a href="http://arts.mit.edu/" rel="nofollow ugc">Arts at MIT</a>.

Redirect by Custom Field

Changes the URLs pointing to pages and posts which have a "redirect" custom field, using that entry as the URL instead.

Otto Kekäläinen

Viljami Kuosmanen

Onni Hakala

This plugin is useful e.g. if you have a wildcard SSL/TLS certificate for server but not for each site.
If the site is normally at say <code>http://example.org/</code> and you want to have the admin area https protected, but you don’t have a SSL/TLS certificate so that <code>https://example.org/</code> would work, you can define another domain for secure connections.
For example instead of <code>https://example.org/wp-login.php</code> or <code>https://example.org/wp-admin/</code> the user is redirected to <code>https://example.seravo.com/wp-login.php</code> or <code>https://example.seravo.com/wp-admin/</code>.
This plugin works with both normal WordPress installations and WordPress Network installation and is compatible with the WordPress MU Domain Mapping plugin.
The code is optimized to be fast and does not for example do any database lookups or use cookies.
This plugin is made by <a href="https://seravo.com/" rel="nofollow ugc">Seravo Oy</a>, which specializes in open source support services and among others is the only company in Finland to provide <a href="https://seravo.com/" rel="nofollow ugc">WordPress Premium Hosting</a>.
Source available at https://github.com/Seravo/wp-https-domain-alias

HTTPS Domain Alias

Enable your site to have a different domains for HTTP and HTTPS.

Redirect by Custom Field vs HTTPS Domain Alias