GRUB - Multiboot boot loader
EasyBCD - EasyBCD is NeoSmart Technologies multiple award-winning answer to tweaking Windows bootloader.
PLoP Boot Manager - The PLoP Boot Manager is a small program to boot different operating systems.
Grub2Win - Safely dual boot Windows and Linux without touching the Windows MBR.
Boot Repair Disk - A simple tool to recover access to your Operating Systems. * Easy-to-use (repair in 1 click ! )
U-Boot - Das U-Boot (the Universal Bootloader) and Embedded Linux