IDE Insight is a global IDE search mechanism (now cloned by Visual Studio ;-) that has been in Delphi for many years. You enable it with Ctrl + . or F6, which used to open a modal dialog box. In Delphi XE5 the user interface has been reworked, adding the capability to the IDE toolbar, making the UI non-modal, and making it easier to reach (if you don't remember the key combination). You can see it in action below.

All you need to do now is to select the search box on top of the toolbar (by default) and start typing: you'll find components, compiler options, IDE configuration options, code snippets, open files, files in the project or project group, open forms, live bindings, recent files and projects, and much much more. The old key combinations still work, but at the beginning it seems they are doing nothing: just start typing and you're back in business. 

A small change, but useful to make an existing very powerful feature much more visible to the users.