A real nice post. I learnt a lot form it especially about the boolean operators. I'd like to add this one to the commands (regular googlers probably know this), they are great help when looking for info for a project or something and provide (well most of the time) like to deeper and detailed info.
define: Get the word definition for the word suppied. e.g: "define: internet" will return the word definiton for "internet"
One can always get the up to date list of google commands on google.
Google is not a mere search engine. The site is offering other services as well and one of the more popular ones is Gmail. In addition google also offers "Picasa" a freeware image editor, a language translator and more! Look here for a full list...