In the python world, there are a number of alternative python interpreters that add cool additional features. One particularly useful example is bpython, which adds dynamic synt
rib is a modular and light Ruby interactive shell.
It, like Pry, uses Ruby's parser so has consistent behavior with Ruby thus less bugs (e.g. https://stackoverflow.com/a/39271791/474597)
It is modular so one can easily extend it with more functionalities.
It is also still actively maintained as of 2016.
JRuby ships with jirb_swing
, which provides code completion.
There's not much in the area of alternatives to irb, but there are a couple of gems that add useful features to irb.
Most notably wirble, which, among other things, gives you colored output (not input though) and a history that goes beyond the current session.