Setting up the bookmarklet takes just a few seconds and gives a nicely formatted output of the page source, including clickable links.
I find it a little slow to run but useful nonetheless.
In the comments on the OSX Daily article, there is also mention of a service called Snoopy which also allows you to “snoop” on the source code. Again, very useful, although links aren’t clickable.
Useful tools for spying on the code behind websites.