Nail-polish lovers, we know your needs on this site are frequently eclipsed by those of makeup, hair, and skin-care junkies. And for that, we apologize. But we're here to share some news that we think will get us off the hook. From 11 p.m. on August 17 to 11 p.m. on August 18, our friends over at Rescue Beauty Lounge are having a 50%-off sale on polishes. You can pick up an iridescent-aqua bottle from the brand's Italian Summer collection or a bright-and-bold red from its Fan Collection 2.0. The custom R29 nail polishes we've created are also up for grabs. We might be a little biased, but they're pretty major. (Have you seen that cobalt blue?) While the deal does exclude a couple collections, we're sure you'll find some colors to satisfy your nail needs. The sale is 24 hours only, so we suggest acting fast. A deal like this only comes around once in a (cobalt-) blue moon.