In Sublime Text and Visual Studio Code you can select multiple other occurrences of the current selection with CTRL-D (see the first animation in the main slideshow on https://www.sublimetext.com/).

I'm so used to this being available that it now almost feels like a chore to have to do a 'normal' find/replace when I'm editing in LINQPad (I know: First World problem...).

Anyway, it would be amazing if LINQPad gained this capability, as it really speeds things up when hacking about with code.