First things first: you ought to be able to configure any distribution to get low power use. The similarities far outweigh the differences. (And every distro team is working on improved power consumption, so it's not even a matter of motivation.)
First, don't run services you don't care about.
Second, use http://www.linuxpowertop.org/ on your system to find applications that don't care about your power bill. (Last I heard, Gnome Terminal busywaited to find out when it should blink the cursor. I hope that's gone by now...)
Third, if you compile your own kernel, consider e.g.
CONFIG_NO_HZ. It ought to allow the CPU to sleep for longer periods between interrupts.
Fourth, look into the kernel-provided
Documentation/laptops/laptop-mode.txt file. It's a bit dated, but still provides good documentation on how to get good power savings.