Under Lion and hopefully under Snow Leopard for you...

Click on the + sign at the lower left or go to Mailbox -> New Smart Mailbox...

then set the option to "Date Last Viewed"


iMac 2.7 GHz Core i5, 12 GB RAM, OS X 10.9, Int SATA 1 TB, Ext Fire 2 TB / 1 TB / 1 TB / 500 GB / 300 GB
Former MacFixIt Forums member since 11/17/99
www.rhubarbproductions.com