Currently I am exploring the world of ruby. Playing around in the irb you get nice intellisense for like 5.<tab><tab>. I tried many editors/IDEs (mainly gedit, vim, radrails) with a couple of plugins. I kind of do not like the bloated eclipse-style environment but as far as I found out it is the only one providing intellisense.
All I have found for gedit/vim (never tried emacs, actually I cannot remember anyone using emacs for ruby development) are plugins doing completion based on phrases in the same file.
Is there some intellisenselike feature for an editor? In my job I am developing PHP in Eclipse PDT but I would really like to not use a bloated IDE for ruby 🙂
Use Rubymine. Its three killer features are Intellisense, Refactoring and Debugging.