Xanadu(tm)-related:

• Enfilade: implementation of a generic Enfilade, a derivatve of the Rope
• ZZCell: implementation of a ZZStructure, a network with colored edges
• Kaukatcr: a zigzag-based programming language, as described here(mirror)
• SpanOps: various miscellaenous operations for dealing with spanpointers -- specifically useful with EDL-based document formats
• OSMIC: a forking revision tree

Misc:

• ChordRouting: implementation of chord-style routing, wherein hash similarity is used to generate stable paths in distributed content-addressable file storage
• Gopher: a simple server for the gopher protocol