Many sources these days contain a link to a web-based source such as Family Search, Ancestry, Find-a-Grave, etc etc etc.
What if these URLs could be pulled out of a more general text field and stored in their own field?
That "pulling out" might be possible to do automagically if the URL is well-structured, but even if not then manual cut and paste is OK.
Once it is in a separate field then 2 further processing options are opened up:
1 - when looking at a source for some event this field can become clickable to open up the URL in a new browser window
2 - a database validation tool could test every single URL in the database to make sure it still connects to "something", not a broken / dead link, providing a list of broken links for the user to fix.