I've found several options for this.

• hibernate-script
• powersave - this seems to come out of SUSE
• HAL plus gnome-power-management

I haven't yet found a review of these options overlap.

This post is informative about powersave and HAL+gnome-power-management
http://forge.novell.com/pipermail/powersave-devel/2006-June/000589.html