Continuing the bone-shaped design theme started with earlier S125i and S315i audio systems last year, Logitech's new Rechargeable Speaker S715i ($150) offers as strong of a value proposition as the company has brought to market since the Pure-Fi Anywhere series -- an eight-driver speaker with a carrying case, remote control, and eight-hour rechargeable battery for the same price as its past four-driver systems. Streamlined with a new flip-open dockā¦