It is not caffeine! It’s Taurine!
There is a new and awesome application out there for OSX Yosemite! It is called “Taurine” and pauses the energy settings like screensaver, dimming etc. for a specific period of time.
This sounds weird, but its really useful. For example if you read a long article on a website and you don’t want the screensaver to disturb you. Or if you render massive data and normally your computer go to sleep.
For me, this is one of the best little applications on the Mac. And it doesn’t take much space. It puts itself into the status bar and is there for you when you need it.