I have a few essential tools that I need to make sure are on every machine.
Windows Live Writer
I need this tool constantly to help me with my blog posts. Plus, I can sync them to OneDrive so no matter what machine I’m on, I can keep working.
Link to full Install: http://windows.microsoft.com/en-us/windows-live/essentials-install-offline-faq
How to sync to OneDrive: http://weblogs.asp.net/jongalloway/8-windows-live-writer-tips
Remote Server Administration Tools
Since I do Devops/IT work, I need access to the server tools.
I tend to prefer Programmers Notepad, although I know others love Notepad++ http://www.pnotepad.org
I use TFS internally at work, but Git externally. Thankfully, there are some great tools to work with Git on Windows and in PowerShell. I also love the GitHub client which can be used with any Git repository you want.