Clover is a new and exciting open source EFI bootloader. Developed over the past 2 years by a group of developers at Project OS X led by Slice, Clover aims to solve problems inherent in existing OS X installation methods and legacy bootloaders:
Boots troublesome desktop and laptop BIOS/UEFI
Uses native OS X installation media
Ability to patch DSDT/kernel/kexts at boot time
Creates OS X Recovery partition
No boot0 error with 4K Advanced Format drives
Solves multi-boot issues with Linux and Windows 7/8
Solves traditional bootloader NVRAM issues related to iMessage/FaceTime
Clover has a completely different system of configuration with a decidedly steep learning curve. It can be confusing for those who have only ever used the more traditional Chameleon or Chimera.