Here's my little setup. We have a small house, and my wife and I share the office, so I've had to fit a lot of stuff in kind of a small area.
2014 13" Retina Macbook Pro, 2.6, Core i5 with 8 GB ram, connected to a BenQ BL10 monitor running at 2560x1440.
Sometimes I'll pop my laptop open for extra screen space, but I usually run it clam shell, like pictured. I can fit a lot of stuff on that BenQ, it's a pretty decent monitor. I've been really happy with it.
Underneath the monitor stand there's a Wacom Intuos 4 medium graphics tablet, that I use for design. My background is in design, so I can really fly with that thing. I just slide it out when I need it.
I use an Apple bluetooth keyboard and a Razer Orochi bluetooth mouse. There's an Epson scanner on the file cabinet next to my desk, and a cork board to the left that was originally supposed to be for pinning inspirational ideas, but ended up as a display showcase for my 4yo son's drawings that he brings in to me from time to time.
Most of the peripherals are connected via a little USB hub that's under my monitor stand, and plugged into my monitor.
Up top there's a set of M-Audio DX-4's, for tunes. I paid something like $200 for these speakers close to ten years ago, they are light weight and sound amazing. Can't say enough good about them. There's also 2 Lacie something or other 1TB FW harddrives up there, for local backups, and a 2TB mini USB drive that I use for additional storage. I have it encrypted so I can take it out if I need to.
On the other side of the room, and not pictured, is a couple of printers and a Synology DS 211J with 2 x 2TB's running in a Raid 1 configuration. It's a really cool little box that I need to utilize more. It's mostly just being used to store stuff and geek around on, but I'm able to remote into it and access files that I have stored on it.
Also, just inside the doorway to the room, tucked away in their own little nook, books and skateboards, ahhh.