Apple has released Java for Mac OS X 10.5 Update 7 for Leopard users, updating Mac OS X's J2SE 5.0 to version 1.5.0_24 and Java SE 6 to 1.6.0_20 and delivering "improved reliability, security, and compatibility for J2SE 5.0 and Java SE 6." The only details given revolve around security fixes, so it's probably worth downloading this update even if you don't anticipate using Java applets much. Also note that J2SE 1.4.2 is no longer being updated and remains disabled in this update, which requires Mac OS X 10.5.8. (Free, 122 MB)
Show Recent Items in Snow Leopard
The Recent Items submenu in the Apple menu is handy, but what if you want to work with a file in there in the Finder, rather than open it? Just press Command when that menu is showing, and all the Applications and Documents change to "Show ... in Finder." This feature is new as of Mac OS X 10.6.3 Snow Leopard.