This is a code reordered version of the dynamic ticks patch from Tony Lindgen 
and Tuukka Tikkanen - sorry about spamming your mail boxes with this, but 
thanks for the code. There is significant renewed interest by the lkml 
audience for such a feature which is why I'm butchering your code (sorry 
again if you don't like me doing this). The only real difference between your 
code and this patch is moving the #ifdef'd code out of code paths and putting 
it into dyn-tick specific files. 

This has slightly more build fixes than the last one I posted and boots and 
runs fine on my laptop. So far at absolute idle it appears this pentiumM 1.7 
is claiming to have _25%_ more battery life. I'll need to investigate further 
to see the real power savings. 

My desktop pentium4 did not like the patch erroring with "bad gzip magic 
number" on boot for reasons that aren't obvious to me. This could be related 
to trying gcc 4.0.1 on that box whereas the laptop is on gcc 3.4.4 and is 
working fine.

Cheers,
Con