Very commonly, we use Ruby hashes as a way to emulate keywords args. The approach goes like:
As @0utoftime pointed out recently, this is also possible when using Hashes inside of Arrays:
And, stretching the use even further, mixed in Arrays:
Similar symmetry and sugar is obviously all through the language, but I found this one particularly cool.
Of course, Array also has some tricks:
and a few forms of multi-return