While Mac OS X Jaguar markedly improved -Tabbing your way between applications, there's still plenty of room for enhancement.
It's such an innocent key combination: -Tab. Easy to say, easy to do, easy to type. Innocent it may be, but embroiled with controversy is this little key command; sure, it switches you to the next open application (and -Shift-Tab sends you to the previous one), but still people clamor for more. They want a smart switcher ? one that goes in order of application usage, not Dock order, or even one that understands individual windows within a single application.
In fact, it's not the Alt-Tab, per se, that's at issue. It's the Mac concept of windows belonging to applications rather than existing semiautonomously that causes unrest. While hopping from Mail to Internet Explorer (IE) to BBEdit is a snap, it's simply impossible to alternate between, say, Google residing in its own IE windows and Document1 in Word. Some applications do provide their own local keyboard shortcut ? -~ in both IE and Mail ? but this is a rarity and varies from application to application. Other applications assign windows to -# keys, but who the heck can bear all that in mind while actually trying to get some work done.
At heart, there are two issues: Jaguar (but not previous releases of OS X) allows you to -Tab to go to your previously used application, and applications, not the windows within them, are -Tab destinations. Some attempts have been made to alter -Tab behavior. Here are a few of the highlights:
LiteSwitchX, from Proteron software, is a freeware application switcher (via -Tab in 10.1.x and below, or a configurable combination) and comes with window layering controls, allowing the user to duplicate previous versions of the Mac OS. One such option (there are four) is Classic Finder Windows, which makes all of the Finder windows come forward together (i.e., click on the Desktop and have all your Finder windows pop to the front). Along with window layering, the -Tab application overlay (which looks similar to the Microsoft Windows overlay) can be resized up or down and supports drag-and-drop and contextual menu items.
AppSwitcher, by Michael Ash, is no longer being activitely developed and is usable only under 10.1.x and below. It brings up a horizontal overlay window (like Microsoft Windows and LiteSwitchX), which shows your applications sorted by front to back, in usage order. Like LiteSwitchX, it's free.
Keyboard Maestro comes in a limited Lite edition and a full version at $20. It's more than a simple application switcher, as it allows multiple clipboards and hot keys with multiple actions. Like the other software listed earlier, it can sort running applications in usage order, but also includes the ability to define applications that should always or never be allowed in the list. You can also tweak the overlay window to display vertically, as opposed to the more common horizontal display.
Finally, there's the popular QuicKeys from CESoft, which does far more than mere application switching, allowing you to define macros, hot keys, text insertion, new floating palettes ? the list goes on and on. Available for $79.95, it includes the ability to switch applications, giving you the opportunity to set up a hot key (other than -Tab) that can switch forward, backward, or to the previously running application. Pricey to some, it encompasses the abilities of a number of other utilities.