I've been reworking my vim folding script for Ruby. It stays within the
usability subspace I like (optimized vertical space, sensible foldtext, fold on
classes, methods, etc.), but now it can also fold optionally on if/while and
friends, and also supports folds set with markers. It is now available as a
plugin, so installation is as easy as copying it into ~/.vim/plugin/; the
default mapping is <Leader>f (i.e. \f if you didn't change mapleader).
Here's a few animations comparing it to the 'syntax' and 'marker' methods.
Syntax vs. SimpleFold
Both images correspond to the same files; I've timed them carefully to show equivalent views
(top-level, class-level, method-level) at a time (you might have to reload the page to make
sure they play synchronously). The first one is fdm=syntax, the second is SimpleFold's