Applications’ Open/Save dialogs are a pain to navigate. This action allows a location to be put straight into a dialog without any clicking or dragging. Works with files as well as folders. If Finder is active, it will jump to the location in the current window. Great for one-window Finder usage!
Download and unzip it, put it in ~/Library/Application Support/Quicksilver/Actions/ and relaunch QS. Oh, and make sure ‘Enable access for assistive devices’ is checked in Universal Access of System Preferences.
When an Open/Save dialog is active, grab a file or folder in the first pane, and run ‘Go To Here’ in the second pane.

Pro tip: Check ‘Allow capitalised keys to select the action’ in Prefs>Extras, and use ⇧G to find ‘Go To Here’ in the second pane. Make ⇧G the default for the action. Now, with any location in pane 1, Hitting ⌘⇧G will instantly run the command, and it’s the same ⌘⇧G shortcut that’s baked into Finder and standard app dialogs.
Icon pinched from the User Interface Access plugin. Code pinched from an old AppleScript action that for the life of me I can’t remember the source of. Tested in Lion.