Cashu is amazing privacy on bitcoin on a totally new level .. Check nostr:npub12rv5lskctqxxs2c8rf2zlzc7xx3qpvzs3w4etgemauy9thegr43sf485vg 's posts and talks about it ..

There is a couple others as well like nostr:npub1uq70uqgas9pyhds2zt57kr9se8rg3s68ztphjnq82ts8rzeknmeql7u0c2

& nostr:npub1dx5q2el8nd4eh3eg9t2e25fd7zuqg7zxz6ldkc3uzgh66ss2yc6st288sj