ibm - Add support for IBM ppc64 specific systems
sys-apps/sysvinit:ibm - adds support for hvc consoles
sys-boot/yaboot-static:ibm - Indicate the usage of ibm based ppc64 hardware
sys-boot/yaboot:ibm - Indicate the usage of ibm based ppc64 hardware
sys-kernel/genkernel:ibm - Install IBM pSeries config as default instead of G5 config.

pcmcia - Adds support for PCMCIA slots/devices found on laptop computers
net-dialup/capi4k-utils:pcmcia - Installs capi-pcmcia framework
net-dialup/isdn4k-utils:pcmcia - Install isdn-pcmcia framework

usb - Adds USB support to applications that have optional USB support (e.g. cups)
net-dialup/capi4k-utils:usb - Installs capi-usb framework
net-dialup/isdn4k-utils:usb - Install isdn-usb framework