Why do Leopard printers hang around on the Dock?

I know what you mean about the printer being too darn persistent, actually. It's been sitting on my Dock all day since I printed a few pages earlier this morning. Very annoying as I try to minimize the number of apps I have running at any time so my Dock is clean and uncluttered.

Fortunately, there's a remarkably easy solution, albeit one that might not be obvious.

What you need to do is click - and hold the button down - on the printer icon in the Dock. The menu pops up and you'll see what to do next:

Choose "Auto Quit", then Quit the printer application and it should automatically quit after emptying the queue from now on.

Interestingly, there's no option in the printer utility itself to make this change, no preferences, nothing. If you don't know about the Dock menu option, you're stuck.