Today I wanted to install Haiku Alpha 3 (ISO LiveCD available from http://www.haiku-os.org/get-haiku) on a Windows 7 + Linux + Haiku notebook system (by default with Windows 7 only, where I added also Ubuntu x64), not installing Grub or Haiku’s boot menu or any other boot manager, but the plain and simple Windows default boot manager! Well it was straightforward using the Windows free software EasyBCD (NeoSmart Technologies)!
Pass 1:
Install Haiku from the mastered ISO LiveCD you can get here http://www.haiku-os.org/get-haiku.
Select a partition on your HD and “Initialize” it as BFS as explained here http://www.haiku-os.org/get-haiku/installation-guide (menu Partition>Initialize>Be File System, Write Changes). Name it Haiku. Then close the Drive Setup window and simply proceed installing Haiku in the prepared partition named Haiku. You’re done.
Quit and reboot in Windows 7.
Pass 2:
From Windows 7 execute EasyBCD.
a) select button on the left "Add New Entry"
b) in the above section “Operating Systems” select Linux/BSD
c) select Type: "GRUB (Legacy)"
d) give the OS boot label a name (e.g. “Haiku”)
e) in the Device field select the partition number where you have installed Haiku (seen as FAT16 by EasyBCD)
f) press the button "Add Entry"
g) select “Edit Boot Menu” button on the left, and in this page press the button “Save Settings” (bottom right)
Done 
http://postimage.org/image/326r9dz9g/
You now can happily boot into Haiku using Microsoft ‘Windows Boot Manager’, no need to messy with GRUB or any other bootmanager.
Since 99% of PCs on the Earth have Windows already installed with its own simple boot manager I wondered why not to use it to boot into Haiku instead of wasting time installing and configuring others? Hope this will push more people to easily install and test this very promising new fresh OS!
Tested with EasyBCD 2.1. Haiku ISO LiveCD Alpha 3. Windows 7 x64 preinstalled laptop.