Another ethnic term that should be used with some caution: "Cuban wrench."
It's heard frequently in Miami in the world of auto repairs. A Cuban wrench is, in fact, a hammer. The backstory here is Cuba and it's plethora of old cars that had to be repaired without access to the proper parts. Thus, if a car needed an alternator, one used any alternator one could find, then made it fit (when it didn't) with a Cuban wrench.
Obviously, the term isn't supposed to be an insult. But a non-Cuban using it might come across as insulting, as mocking a Cuban mechanic.
It occurred to me after Kylabelle's comment that the 'ra' in my username might've made that comment confusing. 
