I use Notepad++ for quick editing jobs because it is a very capable editor and it has a quick load time. Works on a thumb drive.
Komodo Edit (Komodo IDE)
I use Komodo Edit a lot when I am working with Python, Perl, VBScript, JScript, or XML files. It works on my Linux system as well which is a great bonus. I like this editor because it more of a development environment and gives me a lot of flexibility in configuration and custom tools.
PowerShell Integrated Script Editor (ISE)
The ISE is in the CTP releases of PowerShell v2 and it is what I tend to use when I am working in PowerShell. It is included in the distribution, is extensible with the custom menue, and it works. It is pretty sparse on features, but I have not really needed much else up to now.
Primal Pad – Relatively new release from Sapien. This is a neat addition to my USB drive. I like that you can customize the toolbar to add custom commands. This might be my new PowerShell editor for times when the ISE is not installed. The link also lists the rest of the community tools provided by SAPIEN.
vi(m) – I am not geek enough to say that I use this as my every day editor, but it is one that is almost always available on my *nix systems so I use it a lot. Also available for Windows.
Others that I have tried, but I don’t come back to often.
Admin Script Editor