QUOTE (Tripredacus @ Sep 11 2008, 10:53 PM)

b. continue my ages-old project of writing a custom MBR to allow bootable hot-keys?
If I may, wheel (and hot water) have already been invented.

Here:
http://www.boot-land.net/forums/?showtopic=334http://mbldr.sourceforge.net/http://sourceforge.net/project/showfiles.php?group_id=162108QUOTE
Features
May boot up to 9 operating systems from primary partitions or logical disks in custom order
MBR boot loader is written in Assembly language and compiled with NASM
Installation/configuration program is written in C language and compiled with free tools (DJGPP under MS-DOS or FreeDOS; GCC under Linux and BSD; MinGW under Windows)
Installation/configuration program could be run under MS-DOS or FreeDOS and requires DPMI extension. Since mbldr 1.38 Linux and BSD are also supported. Since 1.39 Windows is also supported.
Uses text-mode for both boot and installation/configuration modes
Supports MBR backup/restore operations with partition table checks
Supports user-defined boot by pressing a configurable key ("1", "2", etc. or "F1", "F2", etc.) and showing boot timer activity in a form of progress-bar
Supports switching of an active flag on primary partitions
Supports boot timeout with loading of the default operating system (which is also configurable)
Fully customized boot menu indicating timer and default operating system
Supports booting of the operating systems which reside above 1024 cylinder
Hiding of inactive primary partitions (for FAT/FAT32/NTFS) like it is done in PQ PartitionMagic/OS-2 Boot Manager (i.e. only the partition being booted is visible, all others are hidden). This is done to prevent problems happening with MS-DOS and Microsoft Windows when living simultaneously on one hard disk. Please note that if you boot an operating system from logical disk all FAT/NTFS primary partitions will be marked invisible and inactive.
Detects most modern partition types properly (including hidden ones, NTFS, Linux native, LBA partitions, etc.)
It fits into first 446 bytes of a 1st sector on a hard disk, not requiring separate partition to be allocated
Supports all kind of hard disks supported by BIOS: ATA, SATA and SCSI
Customizable interrupt key of a boot timer. It may be useful if the default <Esc> conflicts with a hot-key reserved by BIOS
Development and packaging of mbldr requires only free software: FreeDOS, DJGPP, GCC, InfoZIP, NASM, UPX, wxWidgets, etc.
May be installed on any of the available HDDs found in a system
The installation/configuration program has multilanguage interface
Now, making the wheel rounder (and hot water hotter) may be a great accomplishment

, though 512 bytes, actually:
512-2-(4*16)-4= 458 bytes
(whole size-magic number-4*partition entries-2K/XP/2003/Vista disk signature)
are a rather smallish environment for adding featires.

Cheers,
jaclaz