I've recently gotten into the tweak thing and now I can't imagine my system without the tweaks. Every carefuly placed cone adds to the sonic characteristics of my system. It's fun to play and manipulate the sound. It doesn't necessarily change for the better by switching things around. Sometimes change is just good for change's sake. Better than spending tons of money to upgrade to something that's different. My latest tweak that made a nice difference were Totem Beaks. They actually blew me away and they are on my speakers to stay.
Strangest Tweak?
Bricks atop amps, sandbads atop speakers,snake oil? And i am sure this is only the tip of the iceberg...