[Radiant] How to use a random Ruby gem from within Radiant?

[Andrew Hedges]

Hi. First time posting. Be kind! :-)

I have a stock install of Radiant 0.6.4 up and running, smooth as  
silk.  I want to use a 3rd party Ruby gem sort of as a web service  
from within my site.  How can I integrate it with Radiant?

TIA,
-Andrew
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andrew at hedges.name / http://andrew.hedges.name/