In the rich text editor:
@reapercity
In a comment:
[reapercity](https://chowlings.com/user/reapercity)
For Names and Avatars:
In the rich text editor:
%reapercity
In a comment:
[![reapercity's Avatar](https://chowlings.com/images/avatars/default.jpg)](https://chowlings.com/user/reapercity) [reapercity](https://chowlings.com/user/reapercity)