SSHing into your Gentoo system
Ready, really? So press the power button, and wait a bit. The boot process is a bit slower than with the official firmware. Once the box seems ready (no more disk noise or led activity), try to ping it:
% ping 192.168.1.106
PING 192.168.1.106 (192.168.1.106) 56(84) bytes of data.
64 bytes from 192.168.1.106: icmp_seq=1 ttl=255 time=0.337 ms
64 bytes from 192.168.1.106: icmp_seq=2 ttl=255 time=0.161 ms
64 bytes from 192.168.1.106: icmp_seq=3 ttl=255 time=0.216 ms

--- 192.168.1.106 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2001ms
rtt min/avg/max/mdev = 0.161/0.238/0.337/0.073 ms

Eh, that looks good... Try to SSH now:
% ssh root@192.168.1.106
Password:
Last login: Sun Dec 19 17:34:56 2004 from eusebe
kurobako root #

\o/ Alleluia \o/
Now you can start reading the not yet written Administrate Your Gentoo System howto, to learn how to install new software, either from sources or using binary packages.


Troubleshooting


If your box refuse to boot in OK mode on the Gentoo system, for instance if it only makes the diag led blinking or things like that, you should try random manipulations until it works. This boot system is sometimes capricious, so deal with it (but the good news is that after it has managed to boot fine once, it will boot fine forever). I've had such troubles during one of my test installs, and don't panic, it finally worked. My magic invocation included, in no particular order:
some reboot with the back small button pressed
some more "echo -n "OKOK" > /dev/fl3 ; shutdown -h now" in EM mode (also try "reboot" or "shutdown -r now" instead of the "shutdown -h now")
some changes on hard drive jumpers (from "Master" to "Cable Select")
some longer poweroff period with the box unplugged
If your box boot fine but you can't SSH into it, then it's a network configuration problem. You can probably solve it by rebooting in EM mode, recheck that you've not skipped any steps of this guide, edit some configuration files, and try again. I'm sure you will finally manage to get it work, even if it's not on your first try.
An important note: you can reboot from Gentoo to EM mode by pressing the back button during ~6 seconds.

And in all case, whatever trouble you have, don't hesitate to ask on the forums or even to PM me (TGL).