I can't count how many times I was working on a project and my boss or client would come by and want to see what I had so far. It was such a pain to open files up in Photoshop just to show them off. This is where the Slide Show mode in Bridge really comes in handy. Now you can easily show off your images. It's also a great tool for reviewing your photos after a photo shoot. Not only do you get a huge preview of the photo, but you can also actually do things to them like rotate, rank, or delete them altogether.
Open a folder in Bridge that contains the photos you'd like to see in a slide show.
After you've selected the photos you want to show in the slide show, just choose View>Slide Show. Now, I tend to use the keyboard shortcut here a lot, which is Command-L (PC: Control-L). Just imagine that it's a "lide show" instead of a slide show and that'll make it easier to remember.
Okay, now that you're in Slide Show mode, you can press the Spacebar to start the slide show. The slide show will automatically advance every few seconds (4 seconds by default). You can choose to wait or you can always use the arrow keys to advance to the next slide manually.
While you're in Slide Show mode, there are a bunch of things that you can do to your photos. Just press the H key to show (or hide) a semi-opaque screen that displays the keyboard shortcuts for what's available. Finally, if you want to get out of Slide Show mode, just press the Escape key and that'll bring you back to Bridge.