Added this blog post to get that piece of scrap paper off my desk and also to remember these tips by means of typing them in.
apples oranges Search for pages with both apples and oranges.
apples OR oranges -worms Either or, not others.
"candied apples" Exact phrase.
+fruit filetype:ppt Only the exact word, in PowerPoint presentations.
~fruit site:meals.com Include synonyms, but only on that site.
define:egoism Search after definitions.
BMW 318...328 Search for ranges, e.g. not the bad 316 model.
link:macworld.com Search after sites linking to macworld.com.
info:www.apple.com/se Show information about apple.se.
related:cdon.com Search for similar sites.
**mac*** All words beginning with mac, e.g. macworld, macintosh.
ARN BSL Search for routes between airports.
Harry Potter For books with harry potter, select the book icon.
stocks:AAPL Stock information.
weather Stockholm Search for weather information.
time Cupertino Get the current time for other places.
sunrise Kuusamo Get the sunrise times, try also "sunset".
5*9+(sqrt 10)^3= Evaluate calculations.
10.5 cm in inches Unit conversions.
66 GBP in EUR Currency conversions.
**Shakespeare wrote *** Let Google fill in the blanks.
P.S. Of course, Google has its own help page on this topic.