Q:

How to view inbound relationships

Working with a very large and complex salesforce setup, we have a custom object with several lookup fields to external objects.  These are easy to check. 
I was hoping there would be an easy way to list all fields which "reference" this object (albeit a lookup or a formula). 
I've looked in the Schema Builder, however that just produces an unintelligible mass of lines of which I cannot see how to highlight a single line of differentiate between an "inbound" and "outbound" relationship reference. 
Any thoughts? 

A:

One way is to use workbench, it will list all child relationships for any object:

Workbench uses the force.com Describe methods, they are available in the SOAP API, REST API and Apex.