This is an old NAS not really powerful but useful for low-load works
Linux 2.4 (D-Link)
Original firmware was built using 2.4 branch kernel. Unfortunately with an old kernel like this and d-link stripped distribution a lot of thing can't be done. The community of site http://dsmg600.info had collected a lot of info and written some guides to extend original firmware functionality, for example I wrote a guide to install MLDonkey and I made a package to simplify customizing of this device.
Linux 2.4 (Gentoo/Debian)
Using kexec, modifying bootloader or using chroot technique we was able to use a more complete distribution, however we won't be able to built a working 2.6 kernel, you can find forum problems related to 2.6 compiling.