Know of a "Dirt Cheap" tweak?


I am looking for tweaks to improve the overall sound quality of my audio system. I recently purchased some TPC contact cleaner and it made a believer out of me. I noticed a signicant improvement, as if a veil was lifted my system sounded more clear and transparent. Bass got tighter too. Do you know of any cheap tweaks that have made a SIGNIFICANT improvement to the sound quality of your Hifi system...let us know... :-) Comments welcomed!
kasboot
No need to be snippy, Sabai. I started designing and selling acoustic resonators before acoustic resonators were even a gleam in Franck Tchang’s eye. That’s why I know that a SPL meter is the only real way to determine where resonators should be placed in any room. Now, I'm not saying that using Franck Tchang's diagram won't work, it will. It will get you around 50% of my SPL meter method. 

"Never get behind anyone 100%." - my old Boss at NASA

have a nice day

Now, if you opt to do ALL of the above.....

Cups, tile, bricks, sandbags, BB's, metal plates, floor braces, et all...

Your gear will resemble a construction site that needs 'tidying up', and edging towards my 'steampunk' speakers' in general appearance.

Please post pictures....curious minds need a good laugh. ;)