Hey guys I have come across a interesting piece of information for you all which I think would be very much useful for you all. So here is a glance for you all have a look at it. you can perform the following functions sleep / standby / hibernate / suspend with the help of command line only. I have tested the following commands in Ubuntu 8.04 using my Toshiba laptop. You can also give a try for the same and do let me know if that would be useful for you or not.
For the sleep mode you can enter the following code
for hibernate you can look out for the following codeCode:pmi action suspend
Now if you are interested in Gnome session first then you can use the following command before pmi.Code:pmi action hibernate
With the help of these buttons you can create a button (launcher) on a Gnome panel . isn’t it a great idea. hope you all will like this method.Code:gnome-screensaver-command –lock