What is the Silliest Accessory You Have Ever Seen.

Some guy makes a parabolic-style reflector from thin laths of wood. It sits behind the speakers. It works much like cupping your ears. Not bad until you hear the price. $30,000+.

Got to admit the worst is the GeoffK phone call. At least it was only $60.

With sincere apologies to OP for going off topic.

@millercarbon From Wikipedia, Snowflake is a 2010s derogatory slang term for a person, implying that they have an inflated sense of uniqueness, an unwarranted sense of entitlement, or are overly-emotional, easily offended, and unable to deal with opposing opinions.

Snowflake is especially used by hard learning politically right people to denigrate liberal people .

Ironically Albert Einstein would today be called a snowflake by those disagreeing with his liberal politics.

wsrrsw--Nice.  And you know the meaning of "denigrate", whereas MC seems not to know the meaning of the word "demean."   
But in terms of the specific accessory here, I'm told that listening to music with this in the room will be overly fatiguing unless you paint the edges green.

Green latex paint? Or can you use oil? Day glow? Yeah Day Glow put on with clockwise strokes with micro detail sable brush.

With some bit of seriousness over the years I have looked at some of the more far fetched looking "improvements" and come close...If I could I would build an out building and acoustically treat it.

Who’s to say if some of these things really do or don’t work? They all share the quest to dampen unwanted vibrations.

I'm pickin' up good vibrations
She's giving me the excitations (oom bop bop)
I'm pickin' up good vibrations (good vibrations, oom bop bop)
She's giving me the excitations (excitations, oom bop bop)