Ion3 is a minimal, tiling, tabbing, keyboard-oriented window manager and extensible using Lua. It was removed from macports because its author changed the license to a variant of the LGPL with additional clauses that boil down to: only the core project may use variations on the name ‘Ion’, that anything using the name must keep 28 days current and that anything else is a derived work and must be renamed and not mention the original or the original name. That the author is volatile and abusive might have a lot to do with it being dropped too.

On the other hand, it’s a great keyboard-driven window manager. If you’re still reading along, as of release candidate 20080103 it can still be built and installed under macports without much trouble. Try the following quick hack:

cd /opt/local/var/macports/sources/rsync.macports.org/release/ports/x11/ion3
sudo mv Portfile old.Portfile
sudo wget http://db.macports.org/file_ref/emit/34709 -O Portfile

edit the file and replace the version and checksum lines with:

version           3rc-20080103
checksums         sha1 f2ce01631b67a4d317b608d2173b368bf716a2ce

then build as normal, for example:

sudo port install ion3

Note that these changes will be wiped out if you sync up with the repository so you may want to follow the instructions at the Macports Guide: Local repositories and create a local branch.