I need to Process Markdown at the command line, so there is no real language restriction.
Extra features such as pretty quotes and dashes are a welcome addition. Code blocks are a must, but they are part of the core I think.
I want to output to HTML only, and I’m on a Unix environment.
I’ve been using python with http://www.freewisdom.org/projects/python-markdown/ without any problem so far, and it has a simple extension mechanism.