You might know that some Screen Savers are built with Quartz Composer, included in the OSX Developer Tools (Retro.qtz and Security.qtz are famous examples). Less well known is that there are a bunch (80+) of Quartz Composer compositions living in the System folder that only need to be copied to another folder so they can be selected in the Desktop & Screen Saver preference panel in System Preferences.
If you would like to enjoy these Screen Savers when you are away from the Mac, just follow these steps:
Quit System Preferences, if it is running.
Copy the files you'd like to test from the folder /System/Library/Compositions into your user's Library/Screen Savers folder (create this if necessary). The system will copy automatically if you drag, as you don't have rights to modify the source folder. I've found that these files work quite well:
If you'd like even more screen savers, the Developer Tools includes two additional ones you can use: Retro and Security. Retro takes your screen, gives it a sepia tone, and bounces it up and down. Your friends will run up to you screaming, "You're monitor is broken!" Security simply takes a bunch of pictures from your iSight and displays them in a grid. It really is awesome.
In Mac OS 10.5, the Spotlight search results list (the drop-down, not the Finder's results window) now supports pressing Command-I to view additional information on the highlighted item. In 10.4, one had to press Command-Return to open the enclosing folder before getting info.
Command-Y to Quick Look items would be a more useful feature, but it's curiously absent.
You then need to reboot so that launchd will no longer start them. Since these are in /System/Library, you will need to check after every update to insure that Apple has not added them back in. I am not positive of all the implications of this, but it does stop the indexing of every volume that I mount, and Spotlight does not show up in the menu bar.
In 10.5, there is no spotlight entry in /etc/hostconfig, and there is a note there that states that this file will be going away in the future.
[robg adds: This hint supersedes the info found in this one, which listed the 10.4 method of disabling Spotlight, which doesn't actually work in 10.5]
One down, one to go? Steve Miner somehow managed to figure out how to disable the translucent menu bar. He posted a solution that involved editing a system-level plist, and then commenter Krioni came up with a one-line Terminal command.
Before you try this, realize it (a) requires a restart, and (b) is modifying a system-level variable, and may cause bad things to happen. I tested it on my 10.5 test machine, and it worked as described. However, proceed at your own risk! In Terminal, enter this command:
You'll need to restart your Mac to see the changes, and no, this won't fix the menus. (To reverse this, I imagine you could just repeat it with a 0 at the end, or (for certain) edit the plist file and remove the added key.
I actually found the reworked menubar a bit too bright -- it's literally just a white bar, lacking the subtle 10.4 gradient. That then led me to stumble on Peter Maurer's new Menu Bar Tint, which adds back the gradient (and even lets you go wild with a completely different color scheme, if you wish -- just remember that the stock colors are all full-black, at 0%, 4%, and 10% opacity levels). That's my menu bar above, with Menu Bar Tint running to provide the gradient.
Now if someone just figures out how to make those menus solid again...
I discovered that you can now right-click (or control-click) in the title bar of an application to get the Customize Toolbar contextual menu. This especially comes in handy while using programs like Safari, where you cannot Command-Option-Click the Hide Toolbar button (because there isn't one) to achieve the same effect.
Tiger had the ability to right-click in the tool bar, but now it works in the title bar as well. This makes a difference when your toolbar doesn't have the convenience of a large empty space to in which to right-click in (i.e. Safari).
In previous versions of the Mac OS, an easy way to activate the screen saver was to trigger the ScreenSaverEngine application. In 10.5, though, there appears to be an issue with this technique.
If you also have the screen saver to come on after a set amount of time, the screensaver will dutifully activate at that time, even if it is already active. This results in some very interesting visuals, and a lot of GPU-churning as two copies of the screen saver vie for attention.
One solution I've found for this -- a technique that still allows you to put an executable in your dock, create a keyboard shortcut, etc., -- is to simply create an Automator action to activate the screensaver. Just open Automator, select Custom, select the Utilities category, and create a workflow consisting of the Start Screen Saver action. Save this workflow as an application, and you now have a tiny application that will activate the screen saver when clicked. Screensavers activated in this way do not seem to suffer from the double-saver syndrome.
It's no secret that the transparent menu bar is unpopular. Since I keep a bare minimum of stuff in my menu bar, I decided to get rid of it altogether. The Info.plist trick detailed in this hint works in Leopard. Note that somewhere in the comments it's pointed out that you need to move the app before opening it again with a hidden menu bar to bypass some cached files.
Much to my amazement, though, when you mouse over the menu bar after using this trick, the menu bar reappears fully opaque. Obviously this isn't a solution for everyone, especially menu bar junkies, but hopefully someone that knows more than me can figure out why this happens and how to make it the default.
[robg adds: I tried this on the 10.5 Finder, and it definitely creates an opaque menu bar. As with 10.4, though, Spotlight breaks. Still, perhaps some dtrace expert can figure out why the menu bar is coming back opaque when used in this manner. Sadly, the menus themselves are still translucent.]
The same Resources directory has two interesting .plist files as well. StdExclusions.plist contains a list of all the folders and files that won't be backed up, while System.plist appears to be a list of all the files that are considered part of the standard release of OS X.
The fvimagetool app in that directory is probably the command which builds temporary disk images when you are doing backups over the network, but I haven't investigated that one fully yet.
[robg adds: While it's easy to start a backup now if you're in the GUI (control-click on the Time Machine icon in the dock or sidebar and choose Backup Now), the above may be useful to those who would like to start a backup remotely via ssh, or for use in scripting.]
It happens now and then that when you control-click on a file to use the Open With contextual menu, you'll see double entries, and even removed applications, in the list of available applicatiopns. A rebuild of the LaunchServices database is then the solution. (This also happened in Tiger.)
The path to the lsregister command needed for the rebuild has changed in 10.5. As such, the following command rebuilds the database on Leopard:
[robg adds: If you find this happening a lot on your machine, you'll probably find it much simpler to put an alias in your .profile file. You need to create the file in your user's home directory (in Terminal), and a simple way to do that is by typing pico .profile. Then type alias lsrebuild='' into the editor window. Position the cursor between the quotes, paste in the line above, and then save and quit by typing Control-X, Y (to save changes), and pressing Return. Open a new window, and you'll be able to just type lsrebuild to rebuild the database. Feel free to change lsrebuild to whatever name you'd like to use.]