VIDIX (VIDeo Interface for *niX)
A portable interface which was designed and introduced as interface to userspace drivers to provide DGA everywhere where it's possible.
http://vidix.sourceforge.net/

Technical Committee T13 AT Attachment
Responsible for all interface standards relating to the popular AT Attachment (ATA) storage interface utilized as the disk drive interface on most personal and mobile computers today.
http://www.t13.org/

Art Interface Device
This page is the home page for the Art Interface Device, an open source hardware project produced in co-operation with Interaccess Electronic Media Arts Centre.
http://www.interaccess.org/aid/schedule.html

Tweak
Experimental user interface, possible successor to Squeak Morphic user interface. Has asynchronous event architecture, mixes interface models: class- + prototype-based, MVC + Morphic. [Open Source]
http://tweakproject.org/

Lightflow Rendering Interface
The Lightflow Rendering Interface is an object oriented programming interface to synthetic rendering, which provides a common environment and description language to treat light distribution in three dimensional spaces.
http://www.lightflowtech.com/

Altia - User Interface Design and GUI Software
User interface design software and GUI tools - quickly build virtual prototypes, simulation graphics and deployable code for embedded displays.
http://www.altia.com

Sourcepole: Eiffel Libraries
Small set with descriptions and links including EiffelBDB, an Eiffel interface to the Berkeley DB, Eiffel-mmap, an Eiffel interface to the mmap system, and gtkxmhtml, an Eiffel interface to the GNOME gtk-xmhtml widget.
http://www.sourcepole.com/2003/2/3/eiffel-libraries

Devasys Embedded Systems
Provides USB I2C/IO interface board with 20 bits of digital I/O, and an I2C interface
http://www.devasys.com

Message Passing Interface
Interface standard, tutorials, libraries, and links to other resources, as well as MPICH, an implementation of MPI.
http://www-unix.mcs.anl.gov/mpi/

Interface '02
The 34th Symposium on the Interface of Computing Science and Statistics. Montreal, Canada; 17--20 April 2002.
http://www.galaxy.gmu.edu/interface/2002.html