http://www.staffandline.com/

Great tool very scalable accross domains/forests/OS etc etc

All the questions you posed are under the assum,ptions that you use scripts to shutdown machines rather than a program to manage shutdown. - Nightwatchman http://www.1e.com/softwareproducts/NightWatchman/Index.aspx allows you to manage shutdown (defer shutdown if you want to connect to your Pc from home or leave some certain PC's as exceptions to the rule.) -Coupled with Wake-on-LAN you can turn PC's on at a certain time (say 5am so the virus scanner can run before uses get in to work) -it allows you to set a schedule so updates can be run before it shuts down. -bonus: it allows for a "clean" shutdown, that is if a user left documents open it'll save them before shutting down.