I'm a die-hard emacs-and-command-line hacker. Once a year I try to evolve past my 1991 toolset and use an IDE for coding, hoping to find something as transformative as the Smalltalk 80 environment. The various Java IDEs never worked for me, even VisualAge. Visual Studio is great, but I don't program for Windows much. Most of my coding is Python. So for my latest project I decided to finally try a Python IDE. After an abortive attempt with Eclipse + PyDev I settled on good ol' Wing IDE. Which is great, and I'm ready to pony up $180 for a license.
The key thing about Wing is that it works very well for Python and Python alone. This is not the IDE for a multilanguage product. But if you want a simple path into running a quick Python hack, with room to expand to complex Python projects, it's very good. Note you need the full professional version to get the important features.
The key feature of Wing is good integration to the Python interpreter. There's a Python shell built right in for interactive hacking. And you can interrupt or breakpoint a running program to examine variables on the stack or execute new code in the process context (great for exploring state). The underlying integration is built right into Python and I'm sure emacs, Eclipse, etc can drive it too. But I could never make it work productively for me, whereas with Wing it works right out of the box.
Of course Wing has all the basic IDE stuff: indenting editor, syntax highlighting, code completion, etc. There's code analysis for contextual help, although without static typing it's a a bit awkward. There's also some tacked on unit testing and revision control support, adequate but not great. Honestly the whole IDE suffers a bit from having a Python hacker's idea of good user interface, but the quality of the interpreter integration is good enough to make up for any rough edges in the UI.
I still need a command line. For Windows Vista it's good ol' Cygwin for a Unix-like environment along with PuTTYcyg for a terminal emulator. (Note that stock Python doesn't work well with Cygwin TTYs, but it's usable.) I finally have a way to hack as efficiently as I used to in Unix, but driven mostly from the Windows machine in front of me instead of via remote sessions. It's pretty nice.