Sending ARP request to unicast MAC instead of broadcast MAC address?

OK, this sounds Really Wacky (or, Really Hacky if you're into puns) but there's a reason for it, I swear... Will typical OSS UNIX kernels (Linux, BSD, MacOS X, etc) reply to a crafted ARP request that, instead of having FF:FF:FF:FF:FF:FF as its destination MAC address, is instead sent to the already-known unicast MAC address of the host? Next, what would be your utility of choice for crafting such a packet? Or is this something one would need to code up by hand in a lower-level language? Thanks, -C