I loved this article from Mac|Life, hope some of you will find it interesting too.

80 OS X Mountain Lion Tips and Tricks | Mac|Life (http://www.maclife.com/article/howtos/80_os_x_mountain_lion_tips_and_tricks)

Lots of stuff in here to play with - lots of stuff I didn't know yet!

Not a tip or trick, but an observation: I use Mail in the three-column layout (mailboxes left, message list centre, message preview right). When you multiple-select messages in the message list (either using the click-shift-click or command-click-click-click), the preview window to the right will stack the messages on top of one another with a slight rotation to the page. Cute!

thanks for the link