By now most people have heard of, and to a degree: understood, the core principles of Bitcoin and proof-of-work based blockchains. But the past few years have brought us a larger universe of related technologies, inhabited by "crypto" enthusiasts. This talk will venture beyond the basic Bitcoin blockchain to explain more advanced (and/or simpler) projects, and skeptically evaluate their uses. Spoiler: There Are None. I will introduce a number of fascinating and intellectually engaging protocols and concepts, from Decentralized Finance (DeFi) to Self-Sovereign Identities (SSI) to Non-Fungible Tokens (NFT), in a way that is both technically accurate and unflattering. As it will turn out, there really is not a single thing that can be solved with a blockchain that cannot better be solved in another way, except maybe for a single worldwide currency with low transaction rates and humongous externalized costs. Still, the things are out there, draw in extreme amounts of engineering and cryptographical prowess, and provide for interesting (and at times: hilariously funny) case studies. 00:00 Intro 00:16 Herald 00:52 Hi, I'm Henryk 02:42 History 05:36 Po[X] 16:46 (Mis)using Bitcoin 25:23 Ethereum: From DAO to Defi 36:24 IOTA 40:26 SSI 50:49 NFT 57:51 Conclusion 1:00:50 Q&A Session 1:23:52 Outro about this event: https://pretalx.c3voc.de/rc3-2021-r3s/talk/TPVWUE/