A great way to decorate your office and impressive your clients and coworkers is to take a couple of your best vacation photos and have them printed in a large format on canvas.Even a 3 mega pixel photo will blow up to a spectactular piece of art when printed on canvas and then framed. You should be able to get a decent size print on canvas for 25 bucks or so.
You can find plenty of places online to do your prints or maybe there is one just down the street from your home or office.
Once you have it framed it will look more like art than your photo. A couple of these around your office can really spice it up. Since the art is from your photos it will be unique and personal.