The Tips - Mac Kung Fu - page 401

Start by selecting the files you don't want to include in your selection. In my
previous example, that would be the three files that we don't want to copy.
This can be done by holding down COMMAND and selecting them.
Then press and hold the COMMAND key and use the mouse to rubber-band
select all the files—including the three you've already selected. You should
find magic happens—the selection inverts so that files that weren't selected
now are and those that were are automatically unselected. In my example,
97 files would now be selected.
This technique works in Finder's List and Column views too but is difficult
to pull off correctly: you must start the elastic-band selection within the listing
of files and not outside the boundaries of the list, or you'll cancel the original
selections.
Tip 392
Open Duplicates of Dashboard Widgets
Here's a tip that might be obvious to some but mind-blowing to others.
You aren't limited to just one representation of any Dashboard widget. In
other words, you could have as many clocks as you want on the Dashboard,
each showing the time in a different time zone—just repeatedly add new clock
widgets from the Manage Widgets selection at the bottom of the screen.
You could also have several versions of the weather widget showing conditions
at different locations or several versions of the Stickies widget with different
colored notes.
Tip 393
Cue Second-by-Second in Movies
You might already know that if you click the blob within the timeline on the
QuickTime Player controller bar, you can cue back and forth in the movie
you're watching, something known as scrubbing . However, if you click and
hold the blob without moving it, you'll see white bars appear in the timeline.