eCos (Embedded Configurable OS) is an open source, configurable, portable, and royalty-free embedded Real Time Operating System. It is written in C++, provides all the usual OS things. You configure the OS so that the parts you don't need aren't loaded to the embedded system. eCos is released under a modified GPL that allows for its use in embedded systems without having to GPL the embedded application.
Powertweak-Linux is a tool to tune your system to its optimal performance settings. It started life as the replacement for the now obsolete kernel option 'tune PCI bridges', and has been extended to provide more features and support more chipsets. It can also tune network/filesystem performance using /proc/sys entries, disk elevator settings, and x86 CPU registers (needs 2.2.18 or 2.4.0test kernel), CDROM speeds, hdparm type features, and Sony VAIO backlight. It has both a GTK GUI and a text-based lister.
mapscsi is a Linux SCSI device mapping tool which solves the problem of SCSI device names being allocated in the order of probing. The problem is that when an additional device is added and has a lower host, channel, or ID than existing devices, the other devices will all be shuffled along on the next reboot (i.e. /dev/sdb becomes /dev/sdc, etc.). mapscsi solves this by creating symbolic links to Linux SCSI devices after scanning all SCSI devices, using information probed from the devices and a set of mapping rules containing device templates to dynamically create link names. mapscsi can fetch Fibre Channel world wide names and loop IDs when using Qlogic HBAs with the qla2x00 driver. mapscsi is a simple alternative to devfs, and provides the added ability of including drive information such as vendor/product/Fibre channel address details, PCI location, and serial numbers in device link names. mapscsi is particularily useful in Fibre Channel SAN environments.