For speeding my modeling workflow I created a ergonomic keymap explained here. But the inset tool doesn't have the Modal map like the knife tool. Which allows you to remap his shortcut when activated. How can I access or create this option?
You can always add or change keyboard shortcuts by hovering your mouse over the context in the toolshelf, and by pressing RMB , then choose add (or change) shortcut and enter the desired short cut in the pop up box. Don't forget to save your new shortcut as default by going to user preferences>save user settings.