Here are some examples:
Forced copies
The whole point of Google is generally to adopt the canonical principle, but there are use cases for forcing a recipient of a document you're sending to make a copy of it. If you want to do this, here's how.
Make sure you share the document and are using the share URL:
This is particularly useful for Google Forms, which browsers have a habit of converting into the recipient's geo-located language unless you actively prevent this. Here's how:
Get your sharing permissions correct and view the live form in an incognito window:
After viewform append ?HL=EN where HL stands for Host Language and EN is the abbreviation for English, like so:
Share this link with your intended recipients, and they will see the form in English regardless of their location or browser settings.
Preview only
This is useful if you're sending a document or slideshow and you want to conceal that it has anything to do with Google. All recipients will be able to see is the content. Here's how:
Get the sharing permissions of your document/slideshow correct first:
Get rid of everything after the last forward slash and replace it with the word preview. Google will do the rest and the URL will look like this:
Share this link, and your recipients will see the document or slideshow in preview mode only.
Link to specific slide in Google Slides
Occasionally, you want eyeballs on a specific slide rather than the whole deck. You can do this as shown here:
Get the sharing permissions of the slideshow correct first and call up the URL:
If you have any other useful examples of this sort of thing, let me know in the comments below :-)