Nick Nicholas translated the text of Colossal Cave in 1991. Robin Lee Powell has heroically translated that translation into a working game - see Colossal Cave for that, and also for the Inform Localisation files needed to create your own Lojbanic IF.
Editing
A vim filetype plugin for convenient word-list lookup, auto-lujvoification, and other useful things.
lojban-mode syntax highlighting and other support code for emacs
jbofacki is a jbofihe/camxes CLI shell with Tab-completion of valsi and rafsi, colorized word lookups by literal name or string, etc. Intended for increased fun in exploring the construction of Lojban texts/sentences; also useful as a aid to memory (mi'e la kampu). Requires Python 2.5+, and currently also makfa-cli for generation + update of dictionary data.
vlastezba for automatically creating a glossary, given a text file containing Lojban. Great for making learning texts accessible to those of limited vocabulary.
cmavlasisku is a .NET-based dictionary program that parses vlasisku pages for answers. It supports defining Lojban words, searching by English gloss, searching by rafsi, and listing the contents selma'o. — by Djeikyb
These are abandoned projects or just broken links. If you are the author of one of the projects listed here, and that project is not dead, merely the link is broken, please fix it!