cheat-sheets on a wide verity of topics.

http://www.cheat-sheets.org/

http://www.room362.com/archives/456-ozymandns-tunneling-ssh-over-dns.html

After several different configurations, I have not be able to get a robotstxt to function on a site by site basis. Part of the confusion is that multisite, single db, single codebase, with sites/mysite.com/modules/robotstxt installation instructions are a bit varied and I may just not have gotten the correct combination of tricks (serveralias, synlinks,staged installation of modules...). My primary difficulty is understanding how drupal manages the 'variable' table.

Great breakdown of the 4 choices.

http://drupalzilla.com/tutorial/theming/drupal-custom-front-page