Well, if I ran the zoo, it would be retargetable to multiple graphic modes (I'm going to be running it in ssh+tmux half the time, so I'd prefer curses) and have a mix of vi's modal keybinding style and Emacs's buffer/mark ring/etc. model and extensibility.

Then again, with 2k loc, it shouldn't be that hard to break out the GTK...

UI model nonwithstanding, that's exactly the sort of project that Lua is designed for.

Neat. Let me know if you get there :-)

http://www.vim.org/scripts/script.php?script_id=1234 is handy.. You can also script vim with ruby and more..

http://www.vim.org/htmldoc/if_ruby.html