Custom Spotlight functions

[doobs]

In Spotlight, it is possible to type things like "fact(3)" to compute 3 factorial and "pow(2,3)" to compute 2^3. I would like to write my own functions such as these (e.g., unit conversion). Is this possible? Where are these built-in functions defined? Thanks in advance...

[kainjow]

I don't think so, at least I haven't seen anything to indicate you can do this through a public API.