From the documentation:

Popularity: 25%

Even if the machines are on different operating systems, this is dead easy. On the source machine, simply ‘dump’ the repository:

Then login to the new machine, and set up the new repo:

That’s all there is to it. Then you can of course delete the dump files, the .tgz files, and even the source repo if you are brave.

Popularity: 95%

(Adapted to my needs from the original at http://www.apache-ssl.org/#FAQ)

First, you create the cert:

Then, you edit the site config, adding the following lines:

Then, you restart apache, while crossing your fingers:

Popularity: 25%