The Icon Sets Proposed in the Icon Contest
In 2006, an contest was held to create an original icon set for Haiku to replace the BeOS R5 icons. With the passage of time, much of the content surrounding the event has rotted away, including images of the proposed icon sets. Luckily, the Internet Archive has backups! The Stipi icon set won, with Honey, zuMi and Mc Clintock trailing close behind.
575
Alba
Deborah
Dropline Neu
Garum
Honey
Ikonki
jdawin
Kabuto
Klapaucius
Mc Clintock
Miqlas
Ponkan
Stippi
Tango
zuMi
Sources:
Haiku icon set contest announcement
All of the icons from every set. The images will start failing to load after a while with the 429 Too Many Requests error. Opening the image in a new tab suffices to view it.
Virtual desktop preview of the icon sets. Closing the Wayback Machine header fixes alignment.
Further Reading:
The mailing list contains a nice summary of discussions of the icon sets.