This is a cool little trick that I have been using over the last couple of days. If your screensaver like mine displays a clock, it can be really useful to keep the screensaver running over a period of time. Although you could set the setting of the screensaver from turning off this doesn’t help if you want to use any energy saver options in this energy conscious world.
A long while ago a mentioned about Caffine, its a program that stops your computer from going to sleep. If you set up a hot corner to run your screen saver (System Preferences > Expose) while running Caffine your screen saver will continue to run indefinitely with out being shut off by the energy saver options.
This type of trick is great if you have a laptop with a really short energy saver option to keep the battery charged as long as possible. This type of trick enables you to keep the screensaver running while you walk away and do something. I usually use it to see what time it is while I am on the other side of the room.
Although this trick is simple, it enables you to keep the screensaver running. I like to think of it as a cheap and dirty work around. There is probably better ways of doing this, but its one of the simplest methods I could think of.