Free Boot Managers and Multi-Boot Loaders

GAG The Graphical Boot Manager - Free Boot Manager/Multi-Boot Loader

GAG has many features as a Boot Manager. It can boot nearly all OSes, up to 9. Besides installing it on your hard disk, you can also do it on a floppy drive. You can set timers to boot specific OSes. The configuration menu can be password-protected. It has a SafeBoot feature which allows you to boot your OS even if GAG is accidentally overwritten. GAG supports drives of up to 5 terabytes and this software is released under the GNU GPL License.

GNU GRUB -(Grand Unified Bootloader) - Free Boot Manager/Multi-Boot Loader

This software is the most popular boot loader for Linux distros. It can also boot other OSes very easily.

LILO (Linux Loader) - Free Boot Manager/Multi-Boot Loader

This software has the same capabilities as GRUB. It can load several Oses.

Smart Boot Manager - Free Boot Manager/Multi-Boot Loader

This boot manager has the ability to automatically find bootable partitions and include them in its boot menu. You can also boot this software from CD-ROMs. It can password-protect your partitions and has multiple other options you can tweak.

XOSL (Extended Operating System Loader) Boot Manager - Free Boot Manager/Multi-Boot Loader

This boot manager needs to be installed from real-mode DOS, on its own partition, but once installed, you can boot up to 24 Oses, among which there can be Windows, Linux, Solaris and more. You can password-protect your boot partitions and do much more with it.