A collection of tips and other goodies I’ve read recently about OS X 10.5 Leopard:
The 512×512 icon support gives an already polished operating system an even cleaner look. Try looking at your applications using Quick Look and you’ll see what I mean. Apple even hid a few things in their default icon set, like the Font Book icon (letters are A F K) and a letter written in the TextEdit icon (good overview w/pics here).
You can find all of the default icons for 10.5 at /System » Library » CoreServices » CoreTypes.bundle (right-click and open package contents) » Contents » Resources. (via macosxhints.com)
public.generic-pc.icns is my personal favorite 😉
If you have the developer tools installed you will find two extra screen savers located at /Developer/Examples/Quartz Composer/Compositions/Screen Savers. Copy the two files to /Library/Screen Savers or ~/Library/Screen Savers. The Security screen saver is fun and is actually motion activated.
Photobooth can now make animated GIFs. Handy for buddy icons.
Drives/devices mounted remotely seem to show up in the Shared section of the finder sidebar instead of the Devices section like in 10.4. Until I realized this I was only able to open them using Quicksilver. Turns out you can drag them in the sidebar from Shared to Devices, and the move is even permanent after the drive is removed and then remounted.
Quick Look is pure awesomeness in a bottle.