No stranger to rolling out services in extended beta and temporary projects, Google on Tuesday unveiled its latest “experiment” for Chrome: Spell Up, a browser-based game that uses voice recognition and speech synthesis to help people learn to spell English better. Users can start at any level they want and the point is to build “towers” of words (hence the “Up” of “Spell Up”). The browser speaks words to the user, and he or she must spell it back to the voice. There are variations around this, such as word guessing games, unscrambling words, filling in missing letter blanks and pronouncing things correctly (and from where I played the game, “correctly” seemed to be the Queen’s English). Users are given clues by way of definitions, and you build up credits by spelling things correctly, which you can then use to help yourself when you are at a loss.