Atom

From the Atom.io page:

Atom is a text editor that’s modern, approachable, yet hackable to the core—a tool you can customize to do anything but also use productively without ever touching a config file.

Personally, I have had to edit a config file to setup a proxy, so YMMV.

Atom is also surprisingly full-featured (e.g. plugins, themes, file system browsing) given that it can be installed in a portable configuration and is multi-platform.

Windows Setup

While Atom is multi-platform, I only use it on Windows.

As aforementioned, I tend to use the zipped Atom files along with the PortableApps.com Platform to create a portable base environment. Next, I extract the zipped Atom files into X:\PortableApps\Atom\, as an example.

Then, you’ll need to get the atom-runner package so that you can run the Python programs with an ALT + R key combo. However, atom-runner will not work if you have to input data from terminal, so you will need either the built-in Command Prompt or a PA.com portable enhancement like Console Portable. When you first open Atom, an .atom folder will be created in %USERPROFILE%, this folder will need to be moved into X:\PortableApps\ to keep your settings.

As for Python, I get the embeddable zip files and extract them into X:\PortableApps\CommonFiles\python3\ to continue with the portable theme. If you want different versions of Python, you can make different folders e.g. python2.7, python3.6, python3.5

Finally, the easiest way to get Atom to find your portable Python installation is to use a shebang on the first line of code #! X:\PortableApps\CommonFiles\python3\python.exe