Has there been any inexpensive item that enhanced your system's sound?


For me it was an inexpensive power cord that was laying around for years, a Pangea AC9.  I have it connected to my Yamaha A S2000.  I've tried the stock cord on the Yamaha and then some of my other cords, (Wireworld, VH Flavor 4, Acronlink/Oyaide custom cord and a MAC). I've had lots of amps and integrated amps over the years, and this is the first time the Pangea contributed to making better sound. It surprised me because I had tossed it aside and forgot about it.  Power cord performance is such a crap-shoot and dependent on so many other variables in the audio chain.  Any inexpensive item you've come across that enhanced your system's sound? 
foster_9
agriculturist84 posts05-13-2016 5:48pm"How best do you clean an AC outlet?"

Deoxit and a pipe cleaner might work inside the receptacles. I highly recommend unhooking it first, or pulling corresponding fuse. Be sure nothing gets left behind that can cause an internal arc. Otherwise the 4th of July may come a little early. I would just replace it for some cheap insurance. Unless its one of those $100,000 units. 

I discovered another inexpensive trick. Dynamat-ing the internal sides of source covers. Avoid blocking vents. I can see some potential for improvement there.  
A lot of great feedback here. For me, the best "inexpensive" tweak that I made was buying Solid Tech Feet of Silence. They were recommended to me by a high end audio dealer who actually didn't carry them. He said they will have virtually the same performance characteristics no matter what surface I place them on. He was right- and the vibration reduction markedly improved the soundstage in my system. The better news was I was able to keep the rack I was using which I find aesthetically pleasing (high WAF) and fit my application well. So, I feel like I have the best of both worlds. 

Absolutely consider smartly placed room treatments. Even "free" ones can make a significant difference. Draping a thin tapestry over my flat screen behind my system cleaned up the musical presentation dramatically! $29! As someone wrote earlier, pay attention to first-reflection points. 

Power conditioner (the right power conditioner) and power cords also made a significant impact on my system. However, I would classify them as inexpensive tweaks. 

And don't forget why started down this path in the first place... for the love of music. Cheers!

Thanks Meerzistar.  I think replacing is the best thing as you are really suggesting I think.  I did use Deoxit on all my AC cable connectors and that was a big help.  But I have so far not tried to clean the wall socket receptacles.  And listening to what you say I won't now.  Trouble is I can't replace my receptacles in my rental apartment, so doing this may have to wait.