David Pogue's column in the Times is devoted to tips and tricks for gadgets and software that many people don't know.
He followed up it with a bunch more on the Times website, which in turn is trailed by a host (159 right now) of suggestions from readers.
On the Mac, I use Cmd-i if I want to email the contents of a web page (such as a Pogue column). And then if I want to convert it all to text, strip out graphics and ads, etc., use Shift-Cmd-t. This trick only works with Safari and Apple Mail, AFAIK. It is a major reason why I keep Safari around as my default browser.
Here are a couple more from readers that use Mac features I was aware of in a way I hadn't previously thought of:
A useful trick on the Mac is to use Control-Command-Shift-4 to get the crosshair cursor to draw across a portion of the screen you want to copy to the clipboard, then open Preview and select Command N to open a new window from the contents of the clipboard (the image). Then do a Mail Selected Image from the File menu. While in Preview, you can annotate the screenshot with arrows, text, rectangles, etc. For example, you could copy part of a Google Earth image and then add directions to your home with the annotation features. Preview automatically reduces the size of the image before sending as an email. Works like a charm.
On any Mac system...When a website has a black background, I like the ease of flipping it to white (and back to black afterwards) by holding the Control-Option-Command keys, then tapping the "8" key on the top row.
I hope these prove useful to some of you.