systemd is a replacement for the init daemon for Linux (either System V or BSD-style). It is intended to provide a better framework for expressing services' dependencies, allow more work to be done concurrently at system startup, and to reduce shell overhead.
runit is a cross-platform Unix init scheme with service supervision, a replacement for sysvinit, and other init schemes. It runs on GNU/Linux, *BSD, MacOSX, Solaris, and can easily be adapted to other Unix operating systems.This app doesn't have any features at the moment.
OpenRC is a dependency-based init system that works with the system provided init program, normally /sbin/init. It is not a replacement for /sbin/init. OpenRC is 100% compatible with Gentoo init scripts, which means you can probably find one for the daemons you want to start in...
eudev is a fork of systemd with the aim of isolating udev from any particular flavor of system initialization. This is a project started by Gentoo developers to ensure udev remains system initialization and distribution neutral.This app doesn't have any features at the moment.
Bootchart is a tool for performance analysis and visualization of the GNU/Linux boot process. It shows your boot behaviour including login as a PNG graphic and lets your analize possible bottlenecks. Resource utilization and process information are collected during the boot...
Finit is a small SysV init replacement with process supervision similar to that of daemontools and runit. Its focus is on small and embedded GNU/Linux systems, although fully functional on standard server and desktop installations.This app doesn't have any features at the moment.