The prompt I'm using is powerline. The python rewrite of powerline is in a stable beta right now, and works really nicely. It's designed to be usable as a prompt for various shells along with the traditional vim prompt.
To get decent performance as a zsh prompt, powerline is best used with the experimental python bindings for zsh. There's a pull request open right now to add optional zpython support. Because it removes the need for forking a new process every time the prompt is rendered, it dramatically speeds up performance.
The other two things I'm using right now are zsh-syntax-highlighting, which gives pretty fish-like syntax highlighting as you type commands on the commandline, and zsh-completions, a convenient set of prepackaged zsh completions.
I'm finding I'm happier setting my own aliases and making my own decisions based on various packages than taking a big package someone's already made and paring that down.