ACPI related reference material

I've collected up some nuggets of information which may be useful to help debug various ACPI issues:

1. ACPI debugging tricks and tips
2. ACPI and Windows Management Instrumentation - mainly about WMI enabled hotkeys
3. Battery and ACPI Methods
4. How S3 suspend/resume works and tricks for debugging
5. S4 tricks for debugging

These Wiki pages are "work-in-progress", so I welcome any corrections on factual inaccuracies. A lot of the information has been pieced together either information found on the internet, or from the Linux kernel source, or disassembling many ACPI tables and also from a little bit of reverse engineering.