Many readers will have heard about Arjan van de Ven and Auke Kok's work to boot an ASUS Eee 901 in 5 seconds. Inspired by this work, and because I have the same laptop, I decided to try to reproduce their results.
From the best Debian site on the internet:
So far I have not come very close to their 5 seconds, but I have made some significant improvements compared to the default boot time for Debian on that machine; this article describes what I've done.
Although some of what follows is specific to the Eee 901, most of it isn't and could be applied to other laptops and PCs in general.