One feature that Windows portables have long had that I've wished for in Macs is a suspend-to-disk (aka hibernate) mode, where instead of a normal sleep session the current contents of memory are written to the hard disk and re-read on startup. This allows a user's session to be preserved even if the battery drains completely. This appears to have been added as a fully supported feature on new PowerBooks; now Matt Johnson has published an Open Firmware hack that enables the feature on other machines that came to market in the last two years or so. Thanks to Daring Fireball for the pointer.