web libs

backpacking
generys
iota
netz
yown

database

iorm minimalist orm
couchdba viewserver

misc

ioscgiweb scgi
iowikiwiki in io, sources
ikerake in io
jimirc bot
muunmulti-user unified network
iosnippetssnippets
iciscontinuous integration server
chordallibrary to generate chords
iopackserialization
iospec2rspec-like tool
iostuffutilities
iojsonjson pack/unpack
beanstalk beanstalk client library
iosvnsubversion binding
iopackagepackage manager using git
iographvizbinding for graphviz

List thanks to Sobe