Some tips I've discovered:

If the device is not responding to input, try the camera lens cover. I've had some situations before where I could see my apps doing stuff in the dashboard, but couldn't press anything. The lens cover trick got my inputs working again. It seems to send a low level interrupt that can jolt the kernel back to life.

Constant network transfer (no matter how low bandwidth) over 3G feels like the real battery killer to me. If you are like me and keep an SSH connection open to a screen session, you'd be wise to disable any clocks or other constantly changing elements, and possibly also adjust keep-alive times, etc... I haven't delved deep into this so far, but I think it will effect a big improvement in my battery life, particularly on 3G/GSM.

Some feel us linux user's may have gotten the shaft on simple synchronization, but we are afforded many other advantages from the nature of the platform:

• Per app screen sharing through X11 forwarding: ssh -X me@mydesktop
• Rsync/SSH file synchronization over wifi/3g (this could apply to mac power users as well)
• The knowledge that nearly every desktop app you use on a daily basis has a high potential for being ported, or otherwise usable (chroot) on the n900 in some way