Which IDEs do Rubyists Use?

Rubymine helps my colleagues to navigate around all parts of an application much easier. There is much more overview. For myself I run into the problem that running Rubymine drains the power of the battery of my MBP in less than two hours. So if on I trip, I do not dare to open Rubymine. Soo, iā€™m open for any battery-friendly editors :smile: