Software I've written (mostly, at least):

zzbot

A jabber bot serving funcoeszz requests

nnebs

Neural-network spam filter

yar

Random (email) signature generator

Patches/Contributions to other software (I'll update and publish them soon):

mutt

"list-mail" function, similar to "list-reply" (but for composing new messages)

XEmacs's python-mode

Rudimentary code completion for python-mode

And some other stuff. I'll post them here in time.