One of the things that confused me the most when I switched to the Mac platform was the fact that there's no built-in way to lock the computer manually with a hotkey when walking away from it. This is something that was drilled into me from working in an office full of pranksters where leaving your computer unlocked was virtually a guarantee that you would be hosting a party for all of your co-workers that coming weekend.

It turns out that this is an oversight in Mac OS X, and a 3rd party utility is required to be able to lock your computer with a hotkey. For a simple solution I would suggest installing a very basic preferences pane called LockTight.

LockTight does exactly what you're looking for: assign a specific hotkey that when pressed will lock your Mac, requiring a password to unlock it if you have it configured to require a password to wake from sleep or screen saver (which you should).

Update: Reader Chad reminds us that if you actually want your machine to go to sleep with a keystroke (as opposed to simply locking the screen) you can use the Option-Cmd-Eject key combo.

[via Lifehacker]

Controlling your music while you're working (or playing) on your computer should be virtually seamless. While these days it's almost impossible to buy a keyboard without media keys built-in, there are many users that either don't have media controlling keys on their keyboards, or would simply prefer to keep their hands on the actual keys. While iTunes is not capable of assigning hotkeys on its own, there are a number of iTunes controller applications on the market that can add this functionality.

In my opinion SizzlingKeys deserves to be at the top of the list of iTunes controller apps for its simplicity, reliability, and extra features. SizzlingKeys installs as a preferences pane, and has a very intuitive interface that allows you to choose which functions to enable, and what the hotkeys should be for those functions.

The list of things you can control with hotkeys is fairly comprehensive:

• Play / Pause
• Previous / Next Track
• Volume Down / Up
• Mute / Almost Mute
• Show / Hide iTunes, Playlists, Search
• Set song rating
• Show floater (song information)

In addition SizzlingKeys offers some non-iTunes "extras" that you can control:

• Sleep computer
• Lock computer
• Activate screen saver

The standard version of SizzlingKeys is free, but there is also a Pro version for $5 that includes the ability to skip forwards and back by a customized interval, the ability to toggle shuffle and repeat modes, and the ability to control the system volume.

Today is Data Privacy Day, a global initiative to highlight information security rights and practices, especially among teens, professionals, corporations, and the government.

As part of the celebration, TUAW (along with our sister blog Download Squad) has seven good ideas for you about how to keep your data safe and away from prying eyes with Mac OS X Leopard. Also, be sure to browse TUAW articles filed under Security for other tips and alerts about keeping your data safe.

1: Turn on your firewall

Leopard, as we all know, comes with a built in firewall to prevent other computers from connecting to internet-facing ports on your computer. But: Did you know it's turned off by default?

To turn on your firewall, open System Preferences, and click the Security icon. Then, click the Firewall tab. Make sure either "Allow only essential services" is selected, or you can choose to "set access for specific services and applications" yourself.

You can also use "Stealth Mode": when enabled, computers that send data to blocked ports won't even get acknowledgement that the data was received. To enable Stealth Mode, click the Advanced button on the Firewall tab of the Security preference pane, and click the check box next to "Enable Stealth Mode."

2: Set a screen saver password

A feature popular with Windows users, Mac OS X can also lock your screen when your computer sleeps or when the screen saver comes on. Simply open System Preferences, select Security, and choose the General tab. Click the check box next to "require password to wake this computer from sleep or screen saver," and you're all set.

If you have automatic login enabled and click the "require password" check box, Mac OS X will recommend that you disable automatic login. This means you'll have to enter your password to turn your computer on, too; nefarious nogoodniks won't be able to restart your Mac while the screen saver is on to circumvent the need for a password. Good thinking.

With Halloween only a couple weeks away, it's time to get your Mac into the holiday spirit ... with a screen saver! The free Jack-o-Lantern screen saver from Killer Robots does just that -- without the mess of carving a pumpkin. It has over 25 pre-made designs, but you can also create your own pumpkin designs in Photoshop using the carving template provided by the developer.

The screen saver features a very realistic pumpkin that rotates against a black background. You can control many settings including: seconds between pumpkin design changes, camera rotation, quality, and screen glow. In addition, you can select which designs you want shown. Check out our gallery of screenshots to get a feel for the quality of this awesome screen saver. You can download the screen saver from the developer's website.

If you want even more customization, check out the Icon Factory's Halloween section for free icons (compatible with Candybar from Panic). Do you have another favorite holiday screen saver or icon set you like to use? Let us know in the comments!

Gallery: Jack-o-Lantern Screensaver

If you're in the market for a new screen saver, and enjoy things like tha's DropClock, check out Simon Heys' (less processor-intensive) Word Clock. It's a wonderful typographic screen saver that shows the time in a clever way, and is enjoying a meme echo among designers right now.

It's extremely flexible: you can customize the colors, position and typography of the clock. Plus, it's available in 18 languages. There's a Flickr pool showing it in action.

If you're worried about burn-in, you might want to take a pass, but if you love (a) clocks, (b) typography, and (c) screen savers as much as I do, this might be your lucky day.

Word Clock is universal binary, and freeware.

Glenn Franxman at HackerMojo just put up a Python script that makes pictures pulled from MetroPulse into a screensaver. It's a mere 17 lines of code (which you can easily modify without knowing Python) that run as a cron job, downloading the images into the directory that you specify for the "Choose Folder..." screensaver.

It's a simple, fun way to keep your screensaver interesting using a minimum of tools. There have been similar applications for services like Flickr, such as FlickrSavr or the screensaver that comes with 1001, but the simplicity of just updating the pictures in the screensaver folder is appealing. And a screensaver seems like a perfect application for my previous ideas involving mdfind and sips. By using the simple method Glenn applies in his Python script, and making a few modifications to the "Spotlight Gallery" Perl script, you could make your screen display the last 20 or so images added to your own system. That could truly be a practical use for the idea, depending, of course, on where the most recent images on your system come from. Yes, my mind just went there.

1. Launch System Preferences
2. Click on 'Desktop & Screen Saver' in the 'Personal' row
3. Choose 'Screen Saver'