When I compose riffs or progressions that I want to become signature to a certain song, I prefer to use voicings near the nut. I feel that this area of the neck provides the most power, definition and clarity possible for chords as well as single-line riffs. In fact, many of Queen's signature riffs, like the ones in Tie Your Mother Down, Stone Cold Crazy and It's Late, are played in the open position. One of my favourites is the riff before the verse in Now I'm Here.