Thought this might be of use to someone on here.
I got this with my 5.1 speaker system but I've never had any use for it. It converts an optical audio signal from a TOS cable to a coaxial cable (useful for sound systems like mine that have one of each connection, a 3.5mm, optical and a coaxial, but if you have two optical devices you can connect one of them to the coaxial input using this).
Comes as-new, still sealed in packet, complete with mains adapter. Never used.
These things retail at £15.99, I'm happy to sell for £10 delivered, however I'm currently after a couple of HDMI cables and a new Xbox 360 Elite play and charge kit, so would be willing to trade if you have anything that would be of use to me.
Let me know if you're interested.