Diagraming table relationships with T-SQL

Connect SQL - SQL Server : Tables Relationship Diagram Using TSQL Script

How do you create relationship diagram/report between tables of a given database ? Mostly people use Database Diagram for this purpose, but this can be achieved by TSQL script as following.

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Kind of like ASCII Art but with TSQL? Okay, maybe not, but still I love these kinds of TSQL hacks (and you know how I love diagrams!).