@Pali,

I was thinking about which possibilities U-boot allows to boot kernels which are not locally stored.

AFAIK U-boot doesn't support WLAN networks so tftpboot is out of the question (but would be seriously cool .

Apparently U-boot can use USB mass storage, which would be half as cool, but still very interesting (http://processors.wiki.ti.com/index....ot#USB_Storage).

Obviously this requires host-mode on the N900s side (the PC/stick would contain the kernel to fatload).

Is this supported at all in N900's U-boot, or can you add support for this?

Having host-mode would also allow for USB-Ethernet adapters, and hence tftp, dhcp, nfs, etc.