I wanted to shake up something with falernum tonight (more on falernum another time), so I pulled up a recipe on Internet Cocktail Database called the Royal Bermuda Cocktail.  Ingredients are 1 3/4 oz Barbados rum, 1/2 oz fresh lime juice, 1/4 oz Cointreau, 1/4 oz falernum, and 1/4 tsp sugar.

I didn't have any limes on hand, so I substituted Rose's and left out the sugar.  I also didn't have any Barbados rum (about the only kind I don't have) (and so why am I making this cocktail? you're asking), so I substituted blue cane Rhum Agricole from Haiti. I did have real velvet falernum, and that's made in Barbados, so that makes up for the wrong-island rum.  If you're making a drink with falernum, buy the real stuff, not the cheap American-made version.  Shake all this on ice, strain, etc.

Verdict:  well, fresh lime juice would have been better, but fresh limes make anything taste better.  Falernum tends to be sweet, so you don't really need any other sweetness (though I tend not to like sweet drinks, so don't listen to me necessarily) (just read my blog).  Not a bad cocktail.  I'm low on various varieties of rum right now (I'd like to try it with 10 Cane, one of my favorites), but I'd like to try this cocktail with different ones.  It has potential.