Router cards for V.35,X.21, T1 routers
FacetWin - Unix/Win32 services integration
Printing, file services, terminal emulation, backup, modem management, email server software
Olicom sells a line of Token Ring cards, and provides drivers for a number of operating systems including Linux.
Sells serial cards that include Linux drivers
www.moxa.com MOXA - Multiport serial boards
Vendors of Serial/Keyboard port interoperability hardware.
www.signum.com Signum - Many, many ICEs (Imbedded Circuit Emulators)
They sell a "unified" sound driver system for Linux.
BitWizard Linux Device Driver Service
Give 'em a card, documentation, and an appropriately-sized pile of money, and you'll get a Linux device driver. And it's likely that the device driver will enter the "normal" kernels, eventually.
Home of the "PC Watchdog;" this can shut down or reset your PC in order to ensure a critical system is down for a minimal length of time.
www.networktechinc.com Network Technologies - KVM switches to let mice, keyboards, monitors be used with multiple computers
www.exide.com Exide - Sells UPS solutions
Ultra SCSI Host Adapter with onboard 10/100 Ethernet
"Big" (4 lines by 20 characters) LCD displays that are suited for reporting status information.