On the topic of toy web crypto projects, here's mine: https://emojicrypt.com/
It offers scrypt + aes-gcm, encoded into 256 emoji; all the crypto is in https://github.com/aurorabbit/libemojicrypt/blob/master/prot... (I could have went without a subrepo, but in theory it makes non-web integration or alternate interfaces simple.)
It's based off of ricmoo's scrypt.js, pfrazee's base-emoji, and WebCrypto.
Output contains a header (with N/r parameters), salt, IV, and HMAC. Room for a dozen more protocol versions as well.
It's abandoned, looking for a loving home! Work for some new (and some unimplemented) features is laid out here: https://github.com/aurorabbit/emojicrypt.com/issues