Catia is a JACK Patchbay, with some neat features like A2J bridge support and JACK Transport.
It's supposed to be as simple as possible so it can work nicely on non-Linux platforms.
A screenshot follows:
Catia is available in the KXStudio repositories and ArchLinux AUR ('catia' package in the KXStudio repositories, 'cadence' in AUR).
ArchLinux (AUR)
Debian/Ubuntu (via KXStudio repositories)
Pre-compiled binaries are available for Linux and Windows (part of the Cadence bundle).
Linux 32bit
Linux 64bit
Windows 32bit
The latest source code is hosted on github, together with bug reports, feature requests, etc.
Source code
Bug reports / Feature requests