I've been putting off setting up multisite on my localhost for ages, mostly because in the past I've found getting Apache virtual hosts to work can be a bit tricky: not impossible, but the sort of thing where I could easily lose an hour on a minor thing I've forgotten to do. And after all, with a shiny new iMac and a hard drive whose proportions I can't even remember, why not just 'drush dl' all over again?
But I'm actually working on a multisite project at the moment, and suddenly getting this to work becomes more interesting than having another SVN copy of my code kicking around.
Given multisite can respond to subfolders, I was wondering if this could work when Drupal itself is in a subfolder, like this:
Turns out it can. Suppose you want a new subsite called 'drupal-subsite'. Here's what to do in your webroot: