Originally Posted by QansasjayhawQ
According to Kirchoff's Loop Law, it should work.
There will be an additional drain on any power source as the voltage level generated by the probe will be maintained across both legs of the Y splitter.
There shouldn't be a problem with meat vs. temp probes because the voltage readings are interpreted and processed by algorithms at the end device reading the values, not the probes themselves.
As far as finding one, you should take your probes to Radio Shack and see if you can find a simple splitter or a way to build one.
According to Kirchoff's Loop Law, it should work. I am sure it could be made to work, but I really don't know why you need the same reading from two different devices. It sounds like he is building a money pit instead of a bbq pit.