This post was originally published on December 6, 2015.You never want something until you can't have it. So, each week in The Sell-Out, we're getting the scoop from your favorite retailers on what's selling like crazy. Watch this space to find out what everyone's buying, sign up for wait lists, and keep tabs on restocks.It's no longer a surprise when a killer, limited-edition clothing collaboration sells like crazy — we've seen it time and time again, with everything from Lilly Pulitzer for Target to Balmain for H&M . But nothing could have prepared us for the frenzy that surrounded Rihanna's creeper collection for Puma (the first for the celeb in her new role as the brand's womenswear creative director and global ambassador for women's training) — and it's partly because they're not quite like anything we've seen before.While the stacked platform sole has been a popular trend for a while now, combining it with all the comfy benefits of a sneaker (and in some pretty sick colors, too) is what makes this shoe genius. Shoppers definitely agreed: According to Bad Gal RiRi herself, the first drop of the shoe sold out in just three hours. And when more became available last month, they were completely wiped from Puma's website by the next day.While Puma told us there won't be any more restocks of the current creeper collection (heartbreaking, we know), there's definitely more exciting product to come. And even though the shoe is sold out on the brand's site, it's still available at the link ahead — for now. If they're 86'd by the time you're reading this, we've found six almost-as-rad alternatives to hold you over until Rihanna's next big thing.