Makes your ruby code look awesome.
https://github.com/tdm00/sublime-theme-railscasts
Useful to convert variables/functions from snake_case to camelCase, as I frequently end using snake_case in coffescript.
Just hit ctrl+alt+c (twice here, I don't know why) on selected snake_case to turn it into camelCase.
https://github.com/jdc0589/CaseConversion
Dead-simple alignment of multi-line selections and multiple selections.
Just hit ctrl+alt+a on selection to align variables.
http://wbond.net/sublime_packages/alignment
Autocomplete of html tags with tab key.
http://docs.emmet.io/
Provides great use of git functions inside Sublime Text, by the commands pallete.
https://sublimegit.net/
Provides diff and merge tools for Sublime Text, by ctrl + alt + d key.
http://www.sublimerge.com/
Shows an icon in the gutter area indicating whether a line has been inserted, modified or deleted.
Allows to cycle between changes with the hotkey ctrl + shift + alt + j
If combined with Railscasts color theme, icon colors aren't shown unless the theme is updated (snippet included on Git Gutter's readme).
https://github.com/jisaacks/GitGutter
Formats JSON when hitting ctrl + alt + j (or accessing the option "Pretty JSON: Format (Pretty Print) JSON" in the command pallet).
https://github.com/dzhibas/SublimePrettyJson
Matches a variety of brackets. Very useful to see clearly the current def/class/if-end ruby block.
https://github.com/facelessuser/BracketHighlighter
Integration with Zeal Docs. Just press F1 over a word to open definition on Zeal. Press shift+F1 to open Zeal window.
https://github.com/vaanwd/Zeal
Add/edit (missing native) commands to Command Palette.
https://github.com/twolfson/sublime-edit-command-palette
For keyboard driven file navigation with ctrl+alt+n
https://packagecontrol.io/packages/Sublime%20Files
More options for right-click on sidebar items, like move or duplicate.
https://github.com/titoBouzout/SideBarEnhancements