I've worked on various robotics systems with a need for sub-millisecond clock synchronization across networked computers. I hate leap seconds, but I would rather have a buggy second rather than a buggy day. Within Linux there's kernel support for international atomic time, but there's seemingly no out-of-the-box support for configuring it from userspace.
I wonder whether the next intern's project at g will be the eliminating leap days with speeding up the clock for a week :)
I’d rather use time.cloudflare.com. Given Google’s history, we never know when they might discontinue it and send it to the graveyard.