An anonymous reader writes: A few years back I discovered that even a person of limited soldering skills can create a nifty surround-sound system with the magic of a passive matrix decoder system; the results pleased me and continue to, It's certainly not a big and fancy surround system, but I recommend it highly as a project with a high ratio of satisfaction to effort. (Here's one of the many, many tutorials out there on doing it yourself; it's not the long-forgotten one I actually used, but I like this one better.) I like listening to recorded music sometimes just to hear how a particular playback system sounds, not just to hear the music "as intended." I'd like to find some more audio hacks and tricks like this that are cheap, easy, and fun. Bonus points if they can be done with the assistance of a couple of smart children, without boring them too much. I have access to Goodwill and other thrift stores that are usually overflowing with cheap-and-cheerful gear, to match my toy budget. What mods or fixes would be fun to implement? Are there brands or models of turntable I should look for as the easiest with which to tinker? Are there cool easy-entry projects akin to that surround sound system that I could use to improve my radio reception? I'm not sure what's out there, but I'd like to get some cool use out of the closet-and-a-half I've got filled with speakers and other gear that I can't quite bear to toss, since "it still works."