The new Onkyo ND S1 idock is a good replacement for the Wadia 170 (takes direct digital info like the Wadia) and appears to a tad better at half the price. It can be purchased from a seller in Japan on ebay (where I got mine). It holds an apple ipod/itouch (has inserts for different models), has a better remote control, is smaller, has an on switch, doesn't stop working from light current transients like the Wadia.
It also offers usb input for optional computer input, as well as optical and coaxial audio outputs, and a optional video output.
And did I mention, it sounds beautiful. By the way, the Monarchy classic DIP which I put in line with it, improved the sound even more.