What’s your vote for the most ridiculous, overpriced, and useless tweak?

Audio magazines.  
There are articles I feel the expert writer is concerned with the word count over the content.  Many times has the article had the "I, Me, Mine" focus then wrote about the subject of review.  Unless the information pertains directly with the subject, the writers cuteness and personal life expirences can be omitted.  I have subscribed to many of the magazines since the 70's.  Todays publishers have a difficult time.  

Tweeks come and go.  Some work and others work well for the persons on the other side.  

What about Kemp Electronics Tachyon box of BS. Tachyons don't even exist, and certainly no one is creating them for a hi-fi tweak. If they just said it was a magical box I wouldn't be getting on their case, but to throw out some absurd scientific BS just to get gullible hobbyists to give them money is disgraceful. 

I wouldn’t dismiss tachyons so quickly. Any more than, say, artificial atoms or quantum teleportation. 

from somewhere in cyberspace. OK, Wikipedia, you got me!

“The possibility of particles moving faster-than-light was first proposed by Robert Ehrilch and Arnold Sommerfeld, independently of each other. In the 1967 paper that coined the term,[3]Gerald Feinberg proposed that tachyonic particles could be quanta of a quantum field with imaginary mass. However, it was soon realized that excitations of such imaginary mass fieldsdo not under any circumstances propagate faster than light,[4] and instead the imaginary mass gives rise to an instability known as tachyon condensation.[1] Nevertheless, in modern physics the term "tachyon" often[1][5] refers to imaginary mass fields rather than to faster-than-light particles. Such fields have come to play a significant role in modern physics.

The term comes from the Greek: ταχύ, tachy, meaning "rapid". The complementary particle types are called luxons (which always move at the speed of light) and bradyons (which always move slower than light); both of these particle types are known to exist.”

When I was a kid working in the amusement park I would sometimes work the Carny side of things. You quickly learned who was savvy and who was a mark. Some of the marks knew they were but played along because they were only throwing away peanuts. Some had no clue.
When I had the stripper living with me I saw the same effect. When I took my friends to her shows for free we would always be treated like marks when we walked in. After we let out that we knew somebody in the show we were treated like family instead of schmucks. The deal was that we weren't stupid enough to actually pay money for the show. We were alright.
Think audio is any different?
Really, do you?

Cork turntable mats - replacing the original Linn LP12 mat - what was I thinking! It sounded so bad.