In 1994 Jeff Bonwick presented his Slab Allocator at the USENIX SummerTechnical Conference. Over two decades later Google reports 35-thousand results for "slab allocator". CiteSeerX reports 93 citations. And many modern kernel allocators are based on his design, such as illumos, Linux, and FreeBSD. Jeff's design, along with the original paper, remains just as relevant today as it was 21 years ago. Join me as I tell the tale of the Slab Allocator: where it came from, what it is, why it's important, and where it's going.