In Ruby, a literal of decimal fraction is instantiated as a Float.
I make a patch to modify it so that a literal of decimal fraction without its exponent part is instantiated as a Rational.
The reason why I wrote this patch is that I think most Rubyists don't need to use Float values. Correct use of Float values is difficult for many people, especially most of Rubyists, who aren't well acquainted with floating-point number arithmetic. I want to realize the world that nobody is in trouble with floating-point errors.
I will talk about such a topic in RubyConf 2011. The talk is titled "Float is Legacy". I've got this title from Ujihisa. I love this title.