What do I really adding stuff upon stuff upon stuff??

6xx Mhz is adequate now (look at HP Ipaqs), I only want to go with 10hz GPS, Yaw sensor, more memory and miniDVI because these one are really useful. And takes the N900 a bit into the professional area without touching the price to much.

These chips or external connector won't be that much higher priced as you might think.

I don't need 1024x600 when I travel, it's ok to have 800x480, but I can connect a usual DVI-Monitor. With DVI I can use VGA adpaters too for projectors. But if 1024x600 isn't too expensive, I take 1024x600

And it's even ok if this device can't do too much 3D but playing full usual video formats (for example from Canon digicams, mjpeg or VDR mpeg2).

And the rest is cosmetic (key/keyboard layout) or nearly built-in (USB Host) or is only a matter of compiling mouse support into Xorg. Even the N800 does have full SDHC

So I don't know what you really mean if I adding stuff upon stuff... I don't think so, only faster CPU, better GPS, Yaw sensor, more memory and miniDVI is new. And this isn't possible end of 2008.