Web Based
Cloud 9 is my favorite web IDE. Its text editor does a fabulous job with syntax and error highlighting and it lets me do things from the terminal. Win win!
Text Editors
Notepad++ has been my text editor of choice for a long time. 🙂
IDEs
Visual Studio
Jetbrains Resharper extension for Visual Studio ($, free for students)
*CLion ($, free for students)
Mac
http://sourabhbajaj.com/mac-setup/
* denotes I’ve heard great things but never used!