Is there any chance you could elaborate on this? I'd appreciate it. Even if I don't use it (yet), I'd like to know real world usage apart from launching apps that aren't in your dock (or even are) or finding files.
I don't have too many apps in the dock. Just the ones I know I might drag files into. i.e. photoshop, mail, subler, handbrake, quicktime... And some of the obvious such as finder, safari, mail...
The rest, and I'm talking 100+, I open them all through spotlight. Just hit Command+space and type in the first two letters. It will know what you wanna open based on your usage.
I use it for files too, but not that often. Also, looking for mails or even visited websites is awesome.
I also have some scripts written on bash or some automator tasks that I can quickly launch using spotlight. If I had to put into my dock just my bash scripts... I would have a 50+ icon dock.