Arguably the coolest of all G1 Transformers, Soundwave has always been a fan favorite. It's odd, because his alt mode, a mini-cassette player, or "Walkman" is quite silly, by now extremely dated, and massively non-threatening. But his robot mode is very imposing, alien and impressive, and his characterization in the cartoons along with the sound of his voice add tremendously to his appeal.
Soundwave was the first "large" Transformer I ever received. He's actually the only large G1 from the initial release of Transformers I had as a kid.
His head was the supposed basis for the Decepticon faction symbol.
Something else that added to Soundwave's appeal was the fact that he had his own little army of cassette soldiers. No other Decepticon (besides Megatron) had that many others at his direct bidding, and why Soundwave never took over as Decepticon leader is beyond me. If he had, the Autobots wouldn't have stood a chance.
Something I never knew until a couple years ago, Soundwave's weapons are batteries, and they actually fit inside a faux battery compartment in his back! Neat!
Soundwave came with Buzzsaw, a character never shown in the cartoons (to my knowledge.) He's the exact same figure as Laserbeak, only Buzzsaw is gold instead of red.
Miscolored or misnamed in the cartoons, Soundwave's little blue pal is actually Frenzy. The cartoons designated the blue cassette guy as Rumble.
Frenzy was originally released with Laserbeak. Later on a few more villainous cassettes were released, so by the time I got him Frenzy came with RatBat. I'm pretty sure I was after RatBat anyways, so Frenzy was just a bonus.
Many years later, a friend of mine gave me Ravage. He's in excellent shape, but he's missing his side rockets. He's seriously the coolest of all cassettes.
"Buzzsaw, Frenzy, Ravage, RatBat, Attack!"
The most recent version of Soundwave is in the new cartoon and Animated line of toys. I'm tempted to pick him up, as he is ingeniously depicted as a Scion with a massive sound system, which makes a lot of sense. Unlike a Walkman that grows to gargantuan proportions and has no visible means of self propulsion.