I won't talk here about the difficulties encountered while installing ~amd64
Gentoo on this baby, as most of the components work quite well and
without a problem, but rather about a few tips I had to dig around the
Internet. Some of these tips may apply to other PCs, or other distributions too

External kernel modules to emerge
To get most of the hardware, emerge:
- net-wireless/iwlwifi: even if it's still relatively new, it works much
better than ipw3945 for the wifi! Update: merged in kernel, simply
emerge net-wireless/iwl3945-ucode, and enable iwlwifi in kernel tree
- media-video/linux-uvc: who knows, this webcam may be useful one day
- x11-drivers/nvidia-drivers: yes, it's proprietary, but you need it to try
compiz-fusion (add "options nvidia NVreg_RegistryDwords="PerfLevelSrc=0x2222"
to /etc/modules.d/nvidia to fix flickering in X)
- app-misc/sdricoh_cs: this is a *very* experimental driver for the card
reader (I did not try further though, as I still have an old PCMCIA one that
works fine and fast) ''Update"": turns out you don't need this one, simply use
the "sdhci" module from kernel
Power management
Now, let's get the most of the battery. First some links that will give a
lot of ideas to get a longer battery life:
- Gentoo Power Management Guide
- Intel-sponsored Less
watts site: by the way, emerging powertop definitely is a good idea!
- Mandatory to let your CPU rest while on battery: HRT (tickless system) patch for amd64, apply it to your 2.6.23
gentoo-sources. Update: merged in recent kernels
- A patch to apply to gnome-applets (works fine here, less CPU
wakeups)
By the way, nvidia broke the brightness key shortcuts while in X, but you
can switch to a console (where the keys work!), adjust brightness, and switch
back to X.
Gnome tips
For now, I run Gnome (2.20) on it, here a few fixes. First, the
gnome-power-manager tray icon may not appear from time to time on login. This
is a known problem, also known as bug 188618 to poor Gentoo developers.
(Update) This was fixed by leio (don't forget to thank him), now you just need
to upgrade to gnome-power-manager-2.20.0-r1 (no need to kill and restart g-p-m
manually now). For other distributions, this was accepted usptream, so you
should be fine soon too 
OK, now that we have a battery life monitor, next tweak: if you have kept
the hidden backup partition on this system, gnome will add a nice (completely
useless) icon for it on your desktop. Thanks to the french Ubuntu forums, here
is how to tell HAL to ignore that partition (/dev/sda1 in my case). Create a
file called /etc/hal/fdi/preprobe/10ignore-disks.fdi, with these lines
inside:
<?xml version="1.0" encoding="UTF-8"?>
<deviceinfo version="0.2">
<device>
<match key="block.device" string="/dev/sda1">
<merge key="info.ignore" type="bool">true</merge>
</match>
</device>
</deviceinfo>
And voila, this one will not bother you anymore 
Last thing, if you'd like to enter your password once at gdm screen, without
the need to retype it for gnome-keyring (NetworkManager trying to connect to
the home wifi), and even SSH passphrases, read this great planet post by fellow french conspiracy Gentoo
developer remi.
Another last thing (last one I promise), about NetworkManager: this is a
great tool, but it will work better if you add something like
'RC_PLUG_SERVICES="!net.eth* !net.wlan*"' to /etc/conf.d/rc (so the system does
not try to start the interfaces before networmanager does). Also take a look at
NetworkManagerDispatcher (bug here): this
tool will automate start/stop of services when NetworkManager connects to a
network (openvpn, ntpd, ...)
OK, I've finished now, thanks to the few people that are still reading
