This page reports the minimal consumptions of Thinkpads when idle. This means, in principle: minimum brightness, CPU and GPU at lowest speed, no wifi, hard drive spun down, no pcmcia cards inserted (see details of each entry).
This kind of information has several uses: comparing one's consumption with other that of other people's setups, knowing which model to use as a gateway/file server, etc.
|600E PIII/450||Archlinux 0.8/xfce||8W|
|T41p||Ubuntu 7.04||Undervolted, fglrx, no dri||8.3W|
|T43 (1871)||Debian (Linux 2.6.21, fluxbox)||DRI, alsa (power_save=1), with usb, no networking||10.1W (12.0W with HD)|
|T43 (2669)||Gentoo (2.6.20-gentoo-r5)||Undervolted, fglrx (powerstate=1), DRI, no alsa, no usb modules, no networking||12.7W|