A curated list of Identicons-like (Avatars, Identicons, and Hash Visualization) original ideas and libraries, sorted by date of appearance

RandomArt

The drunken bishop algorithm for OpenSSH RandomArt, by Alexander von Gernler — 2008, based on random art concept of Perrig and Song paper — 1999

Identicon

Identicon, by Don Park — 2007

MonsterID

MonsterID, by Andreas Gohr — 2007

Wavatars

Wavatars, by Shamus Young —  2007

WP-Identicon

WP-Identicon, by Scott Sherrill-Mix —  2007

Retro

Retro, by Gravatar —  2010?

Vash

Vash, by Terrence Cole —  2011

RoboHash

RoboHash, by Colin Davis  —  2011

Stitchies

Stitchy, by Martin Schneider — 2012

Github Identicon

Github Identicon, by Jason Long — 2013

Bubble

Bubble Identicons, by Doug Akridge — 2014

Jdenticon

jdenticon, by Daniel Mester Pirttijärvi — 2014

Blockies

Blockies, by Alex Van de Sande — 2014

Adorable Avatars

Adorable Avatars, by Jim Remsik— 2014

FlatHash

FlatHash, by Roberto Horta — 2014

IdentiHeart

IdentiHeart, by Guillaume Schlipak — 2015

Florash

Florash, by Francois Lafortune — 2015

Jazzicon

Jazzicon, by Dan Finlay — 2016

Ringicon

Ringicon, by Andreas Gohr — 2016

Circular

Circular Identicons, by Agni Flechette  —  2017

Gradient

Gradient Avatars, by Tobias Lins  —  2017

HashIcon

HashIcon, by Richard Schumann — 2018

Hexicon

Hexicon, by Jon Van Oast — 2018

Hydro-Snowflake

Hydro-Snowflake, by Rawad Ahmad Salhab — 2018

Pictogrify

Pictogrify, by Lúcio Rubens — 2018

monKey

monKey, by Amir Hagafny — 2018

Polkadot-Identicon

Polkadot-Identicon, by Pokadot — 2018

LifeHash

LifeHash, by Wolf McNally and Blockchain Commons - 2018

Solacon

Solacon, by Jon Van Oast - 2021

Honorable mention

QR-Code

QR-code, by Denso-Wave — 1994

Letter Avatar

It’s not clear who come first with the First Letter & Initials Avatars concept, (widely used by Google GMail) but there are several open source libraries from 2014, such as LetterAvatar, Letterpic and ngletteravatar

Letter Avatar — 2014

Animal Identicon

Anonymous animals, by Google docs — 20??

Contributing

1. Fork it
2. Create your update branch (git checkout -b my-new-identicon)
3. Commit your changes (git commit -am 'Add some identicon')
4. Push to the branch (git push origin my-new-identicon)
5. Create new Pull Request