Edit: I did not make this, I'm just showing you where to download it.
I havn't tried this but I know some people were looking for one so I thought I would post it.
Description:
This is the Mac OS 10.3 Jaguar Bootscreen for Windows XP SP1 (Home and Professional).
WARNING: ONLY USE WITH SERVICE PACK 1
I've never seen the real thing so don't laugh if you see this and, well, laugh.
Here is the page link to download it. http://www.themexp.org/view_info.php?id=12042
Cool, but how do you know it's the real 10.3 boot screen? It's obviously a mock up someone did. Apple wouldn't release a thing.
That's pretty nice for having not seen the actual screen. If you want to modify it though the light grey area is one solid light grey, almost like the grey used in the forum theme here. The apple logo is smaller as well and it's a solid dark grey, but not quite as dark as you have it. Also, the actual boot screen has the little jaguar throbber that spins as OSX starts up, but since you can't do that in XP you could always just use the static image of the throbber and have it scroll across the bottom as a progress bar. Anyway, it looks nice but if you want it to be more accurate then those changes would help. If I could find a picture of it I'd post it but I haven't seen one on the net anywhere. Good work though. 
I don't know I recon his brushed look would look better, I quite like this bootscreen.
Listen MartinGy2k, (I haven't tried the screen yet) (no sp1) can you do one without any sort of animation?
Just the brushed grey background and the apple, that would be sleek! (and remember to make the screen go black after boot + before login. (some bootscreens go totally white!)
But uhm,.. this would be a personal favour to me I guess, but could you do one for non-sp1?
I could email you the nt*.exe file if you give me a mail address.
I guess I should have said something like I found this at themexp, I never thought anyone would think I made it myself. I just wanted those that wanted to have it to know where to find it. Sorry for the misunderstanding. I guess I could try to improve on it though.
Its cool nonetheless, thanks for the heads up MartinGy2k.
Well I got around to trying it out and it looks OK (not distorted and no white screen) but there is no animation or object. I saw a different one with the same background but no black border on the same site. I'll download it and see what it does.
At least it looks better that windows default!
Who can port them to non-sp1?
Here is a link to a boot screen like the one above but for Windows XP with NO SERVICE PACK 1 ONLY
http://www.themexp.org/view_info.php?id=9991
(server is slow today)
NOTE: The poster of this boot screen didn't specify anything about service packs, but I downloaded it and the properties of the file say 2600 (2600= no sp1)
(service pack1= 2600.1106, so if you download a bootscreen check the version by hovering your pointer over the file)
I hope this helps and does not confuse!
thanks martin!
i tweaked that a lil bit so it wont look brushed.
the real osx looks just like this boot, but not brushed 
again,
thank you!
To Goku, please be sure to let anyone know if what you have is for sp1 or not because if you use the wrong version windows will not boot any more!
Could someone please host this file:
http://www.themexp.org/view_info.php?id=9991
Or mail it to me,.. I have been trying to download for 2 days now, with no luck, 0.001 kb/s. It's driving me insane.
Thank you.
Glitzychiwuawa check your PM. Included is download link from me to you. 
(I use cable)
Thanks man,... I was getting angry with themexp.
Thanks again.
EDIT:
How ironic,... after all that trouble, that screen just turned out to be the default Windows XP, bootscreen!
MartinGy2k, no worries it's no your fault, you run sp1... and could not have tried the file first (the file is non-sp1).
Thanks for you effort man.
If Goku would release his version I'd be really happy!
Glitzychiwuawa, did you boot in safe mode to replace the file or how did you do it? I reeboot in safe mode by pressing F8 key while boot up and select safe mode.
Never mind, you are correct, I just looked at it with reshac and it is default. 
Heh, would you believe that I run an ancient Pentium 500 dell inspiron 7500 laptop, with only 6 gb total disk space?
Partitioned to boot! 2gb Win98, 4gb XP!
I change all XP system files from 98.
Goku, come on bud, do me a favour.
Does anyone have the non-brushed grey bootscreen with the apple logo?
Aqua-Soft Forums