You may or may not be aware that some of the hippie types in Northern California are not fans of common expressions that involve cruelty to animals. The most common expression I’ve heard transformed since moving to the charming little enclave known as the Bay is “to kill two birds with one stone.”
Not cool, not cool at all: Better to say (and I’ve heard people say these unironically–and I must admit I have used one of them) “feed two birds with one seed” or “free two birds with one key.” (I just heard someone attempt to use “pet two rabbits with one hand” the other day, but that seems to miss the mark somewhat.)
I have my own modest proposal, which all must indulge since it is in fact my birthday. I used the phrase “the straw that broke the camel’s back” on Friday (for reasons I won’t get into here). I propose a new, cruelty-free variant: “the plaster that set the camel’s full-body cast.”