Is there any rationalist equivalent of "good luck"? I've tried a few variants, such as "work well", "knock them dead", "we're with you" and certain situation-specific phrasings, but haven't found anything that worked generally - though a hearty "may all the gods of Olympus be with you!" can serve. Not a vitally important point, but it would be nice to have something similarly supportive and yet accurate to say.
Should you also stop saying "goodbye" since the origin of the word is 'God be with you?' Or stop called celestial bodies "planets" because they do not in fact 'wander?' Good to be rational, less good to enshrine rationality against contamination by humanity and language and culture and history.
Here is a rational take on luck (4 page PDF, recommended)...
http://richardwiseman.files.wordpress.com/2011/09/the_luck_factor.pdf
it's a question of live vs. dead metaphors