One of my great Dock tricks (and I use the term 'trick' loosely), no longer works in Leopard. The old 'put a folder in the Dock and get a hierarchical menu' trick has been obsoleted by Stacks. Stacks are pretty, I'll give Apple that, but they aren't as useful to people who have lots of Documents or Apps on their Macs. Good thing for Quay 1.0 has now been released and my hierarchical menus are back!
Not only are they back, but they're better than ever. Quay allows you to set the way the menu is sorted, the size of the icons on that menu, and the look of the Dock icon. Another thing worth noting is that 'Quay folders' appear on the right side of the Dock separator, as they should, and Quay itself doesn't have to be running in order for these 'Quay Menus' to work.
The developer notes that no undocumented APIs are used, and the Dock isn't hacked in anyway. Quay costs €7, and there is no free trial (if you want more than one Quay folder though, you have to pony up the cash).