10 Obscure Google Search Tips from Lifehacker
LifeHacker has a great article on the "Top 10 Obscure Google Search Tricks." Even if you consider yourself a sophisticated Google user, I think you will find some gems in this list. Tips include shortcuts on tracking package shipments, how to get Google to search only faces in an image search, a quick way to get the local time anywhere, and how to convert different forms of measurement (money, weights, temperatures, etc.).