If you have an AWARD BIOS 4.51G, you can replace the standard green EPA logo with a BeOS logo, to be displayed at boot time.
Warning: While many users have reported success with this technique, it is not supported, and may crash your computer. If you have never flashed your BIOS or are afraid to, just don’t do it! In particular, we’ve had one report that a user with an Asus P2B-DS toasted his BIOS. That user was able to get back into fail-safe mode by removing one processor temporarily and using fail-safe mode. This indicates that problems may crop up with dual-CPU machines. Proceed with extreme caution, at your own risk.
First, you need to download the logo image file. Next, you’ll need to grab the utility cbrom.exe. You’ll also need the right BIOS flasher for your motherboard.
Alternatively, you can grab the logo and cbrom utility here:
http://www.solid.cc/belogo/be.epa
http://www.solid.cc/belogo/cbrom.ex e
Boot into DOS and run:

cbrom yourbios.bin /epa BeOS.epa

and you can reflash your BIOS using your flash.exe, pflash.exe or awdflash.exe (check at your motherboard manufacturer’s Web site for the latest BIOS and flasher).
I’ve tested this with an Asus P2L97 with various BIOS versions (1.03 to 1005), and also with 4 or 5 version (including LH) on an Abit BH6. At least one user has reported success with an Asus P5-A.
Note: If something goes wrong during flash, the new Award BIOS handles a special boot block that enables only drive A: and a PCI VGA board, so you can boot from a floppy disk in an emergency. BEFORE flashing your BIOS, create a system disk (format a: /s) and put your original BIOS on it with your awdflash.exe and create an autoexec.bat with

awdflash yourbios.bin /py /sn /cc /cp

This tip is also available in French.