The biggest problem with all Linux systems is: "There is no photoshop". That's why most of us chose to work on macs, or still some microsoft systems.
When I started a new job I got a laptop with Windows 8. I didn't like it, and it didn't like me, and what's even worse, it didn't even have an i3. Solution? Ubuntu. I chose the newest one, number 14, Trusty Tahr. Why this one?
You can do most of the job with Terminal. Git commands, sass, ruby stuff. When you want to install some software, just copy three lines of commands to the terminal and the job is done. I think that terminal is the feature that I love the most. Well, there is one in windows, but somehow, I didn't like it.
I like the design, I like the way it looks, I like the way it works.
Everything works faster with no crashes and slideshow when more than one psd file is opened. And it's stable as hell. If your PC is even slower than mine ( Pentium B960 @ 2.20GHz × 2, 4GB RAM), you can try Xubuntu or Lubuntu which are lighter distributions.
I can focus more on my tasks. I don't really know how this works, but I get job done faster than on win8.
5. It's free!
Nothing to add, download it once and install on as many machines as you want!
Software you ask?
1. There ain't no photoshop
My solution was to use Virtual Box, instal winXP and run photoshop there. And it works, perfectly. For license reasons I run CS4.
2. Code editor
No surprises, Sublime Text, but you can also try Brackets.
Chrome, Opera, Firefox. IE and Safari needs to opened on winXP. Not a big deal.
4. Local PHP server
I use XAMPP and it works just fine on Ubuntu.
5. Archive stuff
Packing and unpacking archives is built-in.
6. FTP Client
There is one built-in, I also use FileZilla.
7. Additional software
Skype, Spotify, Dropbox, GDocs...