I'm a tiBook user, and run most of my life off of that machine, and usually do that in multi-head mode. AOL put this huge ass 22" ViewSonic on my desk and I just plug that into the VGA port, and blammo, there's massive amounts of desktop space, and I use all of it. The tiBook alone is 1152 x 786 and I run the ViewSonic at 1280 x 1024 (I know, I could boost the res, but I like to read from the screen without straining).
The tiBook screen gets reserved for applications that I keep open all day and provide ongoing, and somewhat static, service. This includes Audion (music), Adium (instant massaging), and Terminal which is not really static, but I like having it up at all times. Up at all times you ask? Aren't they like that all the time? Well, no.
ASM is an application switching menu, and I use it for one specific bit of functionality, hiding applications on switch. So, if I have the previously mentioned apps running, and let's say Internet Explorer, Photoshop and BBedit as well, I like to hide other applications when a new one comes to the foreground. It keeps the window clutter to a minimum, which is important, because I usually have about 10 apps open.
Now, here's where it gets good, I exclude Audion, Adium and Terminal (and the Finder) from the hiding-on-switching function. So they remain ever present and visible, and the dock behavior falls in line with the hiding behavior (which you set in ASM). I want to hide the dock when an app comes forward and hides other apps.
I don't want any of the other functionality of ASM, and I don't like the start up bug it has had in every version that I have used. Keyboard Maestro has some of this functionality, but it isn't a PreferencesPane, and runs as an application that installs a daemon, and then you quit the app (bleh). So, Unsanity please step in here, and make a small, OS integrated, targeted hack like you always do. There's $20 in it for you.