Speak & Spell Emulator - Time Waster
Check out Kevin St. Onge's fully-playable Speak & Spell emulator, and take a trip back in time. This thing works exactly as you remember it.
This particular emulator has been around since 2006, but seems to have experienced a resurgence in popularity over the past month or so. I dug through the DLS archives and saw that there used to be another one online, circa 1995. It's since been taken down, so I thought I'd share Kevin's version.
You can play the classic spelling and word-guessing games, but you can't circuit-bend this virtual Speak & Spell, or whack it to make it talk in creepy nonsense words. You'll have to track down a real one for that.