From Trammell Hudson's Projects
The NeXT computers were one of Steve Job's greatest systems. They developed the Objective C language, the Interface Builder things like the Terminal.app application packaging. When Apple bought NeXT, it dumped the older Macintosh OS and turned the user friendly (but still Unix-like) NeXTstep into OS X. Every Mac and iPhone today still remembers this with the name of the classes like NSString in Foundation Kit.
If you don't know the root password, boot into single user mode by holding right Command and numpad ~ after Loading from disk is displayed. Then run bsd -s and wait for the # root prompt. The NetInfo services need to be started, so run sh /etc/rc & to get them going and then you can use passwd root to set the new password.
Configuring the network on the NeXT involves editing /etc/hostconfig. I had to setup a NAT proxy from my laptop's ethernet to wifi, so the configuration was IP 192.168.2.x, netmask 255.255.255.0, broadcast 192.168.2.255. The name server is set in /etc/resolv.conf and you can use 188.8.131.52.
To transfer the files without scp, curl or a webbrowser, you can use a combination of tools to bootstrap. On the proxy laptop I ran:
uuencode ~/Downloads/OmniWeb.1.0.N.b.tar.gz omniweb.tar.gz | nc -l 9999
On the NeXT I ran:
cd /tmp telnet 192.168.2.1 9999 | uudecode gzcat omniweb.tar.gz | tar xvf - mv OmniWeb.app /LocalApps/
Repeat to transfer OmniImageFilter, although it will unpack OmniImageFilter.pkg. Double click it in the Finder and it will install the image rendering tools. You will have to log out and back in for these changes to take effect.
OmniWeb speaks HTTP/1.0, which means that it doesn't send the Host: header and won't work with modern web servers. You will also need jwz's http10proxy to add headers to the requests to make them work with HTTP/1.1 servers. After setting the proxy in the OmniWeb preferences, restart it one more time and hopefully now everything will work.