This tutorial video from March 2012:
http://www.youtube.com/watch?v=dynPx1B0jis

shows a page at URL:
http://codeigniter.com/wiki/mod_rewrite

(at about 5 mins in) which no longer exists. It appears to have some different mod_write settings to what I can find in the forums (eg http://ellislab.com/forums/viewthread/119491/), and I can’t see a page in the wiki about it.

Straining my eyes at the text in the tutorial video, it appears to have these lines added:
  RewriteCond %{REQUEST_URI} ^application.*
  RewriteRule ^(.*)$ /index.php/$1 [L]

Can anyone tell me why the wiki page is gone, as I’ve wasted a lot of time trying to understand the settings I need to use. Thanks!

The wiki was moved to Github. Who knows why that particular article is now missing - maybe the author removed it, maybe someone else did. Who knows.

There is a LOT of info about mod rewrite on these forums and via Google, since it can differ quite a bit between environments. I’m sure one will help you.