One small bump in the road when working with HAML is having to convert HTML snippets (e.g. from the Bootstrap docs) to HAML.
The html2haml gem handles the conversion:
gem install html2haml
Once installed, you can use a pair of very useful utilities that come with OSX: pbcopy and pbpaste. The former copies what it reads from stdin to the clipboard, and the latter dumps the clipboard to stdout.
Putting these three together, copying HTML into the clipboard and pasting it as HAML is easy. Once the HTML is copied, run:
pbpaste | html2haml | pbcopy
pbpaste writes the copied HTML to stdin, html2haml converts it to HAML, and pbcopy puts the HAML back in to the clipboard.