I use link nodes a lot, nothing like the monstrosity that bakman2 has done above. 
If I have a flow that does one job, it will have wires throughout.
Where I use them the most is for timers as I posted here previously, and common linking outputs - alerting, flow logging.
Oh, also make sure you name your link node pairs/partners, it helps with debugging. I also change the icons to match too.
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