It's easy to never go beyond the basics of Open and Save dialog boxes, despite their being perhaps the most-used feature of the Mac interface. Instead of simply working with the basics, make these dialog boxes work for you. (The last two tips here are Snow Leopard-only.)
1. Use Spotlight to search for missing files
You go to open that Quarterly Report you just copied over from a thumb drive, but you've totally forgotten where you put it. Let Spotlight come to the rescue, right in the Open dialog box. You don't even have to reach for your mouse: Activate the Spotlight field by pressing Command-F, and then type in the search term for a file or a folder that you've misplaced. (There's a Spotlight field in the Save dialog box, too.)
Using Spotlight keywords makes searching from within these dialog boxes even more efficient. These special terms limit your searches so that you don't get as many unwanted results. For example, instead of typing quarterly in the search field when you're looking for that report, type name:quarterly so you won't find documents that simply contain the word quarterly. (When you use keywords, make sure there's no space between the keyword and the colon that follows it; you can leave a space after the colon.)
The two keywords I use most are name and kind. Use name to limit a search to only file names (instead of also looking through a document's contents). Use kind to specify the file type. When I'm looking specifically for a folder, I type kind:folder FolderName or FolderName kind:folder to avoid scrolling through a long list that includes files with similar names.
2. Customize your sidebar on-the-fly
The Finder's sidebar gives you one-click access to items you use frequently: Click on a sidebar folder, and the folder opens. You'll find the same click-and-you're-there convenience in every Open and Save dialog box. But it's there I often notice a sidebar organizational problem. ("I need this new folder in the sidebar"; "This folder should be at the top now because I'm using it so much"; "I haven't used that folder for weeks, it's in my way.")
Fortunately, the sidebar in an Open/Save dialog box is not merely a static reflection of the one you set up in Finder windows. Redesign the sidebar's Places category from within a dialog box just as you would in the Finder. Add a folder by dragging it from the window's list to a spot in the sidebar. Reorder items by dragging them up or down to new positions. Remove an item by dragging it out of the sidebar and letting go.
3. Save time by opening multiple items at once
You need to open three items in Microsoft Word, or two in Adobe InDesign, or any number in some other application. Unfortunately, you're already in the Open dialog box and don't want to switch into the Finder. No problem. If you can see the items you want to open, select all of them, and then press Return or click on the dialog box's Open button to open all the files at once.
How you select multiple items depends on what Finder view(Icon, List, and Column) you're using in the dialog box. (Change your view by clicking on the small buttons at the top of the dialog box, or by pressing Command-1, Command-2, or Command-3.) If you're in List or Column view, you can click on the first item and then Shift-click on the last to select them and everything in between. Alternatively, Command-click to select noncontiguous items. In Icon view, you can also drag a selection rectangle around icons to select them, using a Shift-click afterward to add an item to, or remove it from, the selection.
Tip If you're in the List view, you can select and open multiple items that aren't even in the same folder, as long as you can expand the folders to a level that displays all the items you want.
4. Take advantage of Quick Look
When you want to preview a file without opening it, nothing beats Quick Look. Luckily, you can use Quick Look when you're in an Open dialog box. This is especially helpful if you need to see a file that the application you're in doesn't open, such as when you're placing a document into InDesign or a graphic in a Word document.
In Leopard, you need a special Automator droplet described in Mac OS X Hints. But in Snow Leopard, you can use Quick Look the same way you do in the Finder. Just select an item in the dialog box and then press the spacebar. If you select multiple items, the Quick Look window provides a slideshow option. But, as in the Finder, you don't need the slideshow to easily see a sequence of files: use the Up or Down Arrow key to select the previous or next item in the dialog box's list, and the Quick Look window updates immediately.
5. Customize the columns you see in List view
Feeling restricted by the same old three-column setup in your Open and Save dialog boxes? Although the default columns—Name, Date Modified, and Size—are useful, sometimes you'd benefit more from a Date Created or Last Opened column. You can have these columns, and a few more, in Snow Leopard. With the dialog box in list view, Control-click on a column header for a contextual menu of column choices.
Custom Snow Leopard column headers
The addition of column headers in Snow Leopard's Open and Save dialog boxes isn't just cosmetic: Control-click on the header to access a contextual menu that lets you choose which columns will be displayed.
Once you have the columns you need, sort, rearrange, and resize them the same way as in a Finder-window list view. When you need more room in the dialog box to see all your columns, drag the bottom-right corner to resize it. These changes are application-specific, so you have to design your dialog boxes for each program; but, once you set them, they remain that way until you change them again.
This story, "Snow Leopard: Five secrets of Open and Save dialog boxes" was originally published by Macworld.