I've been experimenting with a fairly new addition to Photoshop: the PixelSquid plugin. The plugin allows you to download 3D objects from PixelSquid.com and add them to a Photoshop document.
Almost everything in the image above is from PixelSquid, even the oriental carpet on the floor. The modern geometric wallpaper and the flooring are images of patterns which I manipulated in Photoshop. The laptop monitor is showing a screen capture of a Lightroom screen from my own desktop PC.
You can create a free PixelSquid account and then download up to 100 free high-quality images. Once you exceed 100 images, you'll either have to pay or use the free, but watermarked and cross-hatched objects. That's what I did for the above image. If you choose to pay, it costs either $7.95 per 3D object or $14.99 per month for unlimited access to all the objects.
Once you've created your account and installed the Photoshop plugin, it's easy to create high-quality images. For my image, I first added the desk to my composition. In the plugin, I rotated the desk to the angle I wanted. Next, I added the chair. The chair was too big for the desk, so after rotating it I used Photoshop's transform tool to scale it to the right size. The chair ended up behind the desk, so I used the plugin to bring it to the front. I did the same with all the other objects. For the rug, after sizing it and orientating it properly, I used Photoshop's perspective transform tool to make it appear to recede into the distance.
The whole composition took about a half-hour to create and I had a lot of fun doing it. And please ignore the cross-hatches: I'll remove those once I pay. After working on this image, I think it will be worth it.
Go to PixelSquid.com to see their collections of thousands of 3D objects learn more about using them in your compositions.