Here’s a quick but useful tip for those who love their desktop backgrounds and change them on a regular basis.
Choosing a new wallpaper in the Desktop & Screen Saver pane of System Preferences? If your Mac has a multitouch trackpad, place the mouse cursor over the thumbnail previews of the wallpapers and use the pinch-and-expand gesture, normally used to zoom in and out of photos in Preview or on the iPad, to make the thumbnails larger and smaller.
Give it a try–it’s pretty neat!