GAG - Graphical Boot Manager - An open source graphical boot manager which supports up to 9 operating systems. Screen shots, version history and download.
MasterBooter - Boot manager which can be used to install and maintain operating systems on a PC. Supports many operating systems. Shareware and registered versions available.
MATTsoft Boot Manager: MBTMGR - Boots multiple OSs, including several on one FAT partition. Download, installation documents.
Netboot - Includes boot manager functionality and boots Linux, DOS and FreeBSD via a TCP/IP network using BOOTP and TFTP.
OSL2000 - A universal boot manager allowing selection from a number of operating systems. Includes support for booting from USB, CDROM and other devices.
SOLO: Shag/Os LOader - Boot loader for Shag/OS which also supports, Linux and other PC operating systems. Includes source.
SyMon - Boot manager with support of up to 36 primary partitions,
SysLinux - Home of SysLinux (floppy), PXELinux (network), ISOLinux (CD-ROM), ExtLinux (ext2/3) utilities to boot Linux kernel; MemDisk, tool to boot legacy OSs (e.g., DOS) from nontraditional media.
zBoot Manager - An effective boot manager, which allows the easy install and use of multiple operating systems on a single hard drive. Directly install other OSs to extended partitions and logic drivers.