TV/RF splitter should to it for each device.
Technically, you will need active buffering to do this. S/PDIF is specified as a point-to-point transmission-line, so it is designed to go to exactly one destination, not two. It is both source and parallel terminated, so this complicates things as well. There is no way that you can maintain a 75 ohm impedance to two destinations.
Steve is correct -- the only way to do this properly is with active buffering. TV/RF splitters would (kind of) preserve the impedance, but they are designed for frequencies above 50MHz in an application where transient response isn't critical, and even if this weren't the case, there's still at least 3.5 dB of signal loss . . . not something you want to do to an S/PDIF signal.
Professional-quality composite-video distribution and switching devices are generally a good choice for this. Specifically for splitting S/PDIF and Dolby AC3, I have used the Extron MDA-3V "Mini Distribution Amplifier" with excellent results.