If you place the cursor on an identifier (variable/function name/etc), CnPack will show you where that identifier is used in your code. Look for example how easy it is to spot where the FBuffPos variable is used in the code below:
Also, see how “dangerous” instructions (“Exit”) have been marked in blue!
Note: On your Delphi installation, the colors might differ because I customized my CnPack plugin to my liking.
Update: Now, Delphi 12 can also do this trick – but still CnPack is more customizable. To enable it, go to Options -> Editor and activate Highlight words -> By cursor.
Read more about this kind of customizations in my “Delphi in all its glory” books.