Tweaks you got rid of because they were not effective (enough)?

There are some audiophiles for whom cost is no object; they buy what they wish and every single tweak and gadget which promises to improve the sound. And the industry is all too happy to produce such tweaks -- often made of expensive materials with elaborate engineering explanations. Those who question the value of these tweaks are frequently accused of being "naysayers" who are either too ignorant or insensate to realize that "everything matters."

Of course, money spent one place cannot be spent elsewhere; expenditures on tweaks take the place of other more central factors affecting the sound. In some cases, those tweaks are worth it; you can hear the difference, and that $400 (or whatever) really could not have improved your speakers or sub or amp, etc.

So, the question here is simple: Which tweak have you tried which, after some experience and reflection, you realized was either *not* effective or not the most effective way to improve your system? 
@mahgister -- It's all good. Thanks for your nice comment above.

@jerrybj Which tweaks did you get rid of because they made no discernible difference?
Expensive Fuses
Good one....I will add turning around fuses and trying to hear a difference
I have tried a number of tweaks over the years but few have remained in my system. They might sound good one day and sound worse the next. The ones that have survived are based on sound Engineering concepts like resonance and vibration control.

Also, sometimes a tweak to address problem A introduces problem B. A good example of this is the use of ferrite cores on power cords. They do reduce the amount of RF coming in on the AC supply but, unfortunately, increase the AC source impedance as seen by the device. Power amps (and integrated amps) are susceptible and may become current-starved during dynamic conditions with a negative effect on sound quality. 
No comment on Vibrapods’ efficacy, but the nasty residue can be prevented by placing a piece of plastic sandwich baggie between the Vibrapod and surface. Same with sorbothane. Perhaps Vibrapods are made of sorbothane?
I'm pretty sure that's exactly what they are.  I put some construction paper between them and components, but only after they left stains on one of my components.  I stopped using them.  I've had better luck using hockey pucks.