It does more than wake you up in the morning.  Coffee has been linked to reduced prostate cancer deaths (by as much as 60%!) http://jnci.oxfordjournals.org.....20-ae7d-09fcd2b2224e  It may reduce the risk of Alzheimer's.  http://news.theage.com.au/brea.....y-20090116-7in8.html  It can even act as an anti-oxident.  http://www.independent.co.uk/l.....oxidants-504669.html

However, more than 3 cups a day can cause hallucinations.  http://www.telegraph.co.uk/sci.....-hallucinations.html  Or can increase heart disease if you have the wrong gene. http://www.nature.com/news/2006/060306/full/news060306-9.html

There's also research that suggests that drinking coffee in conjunction with fatty foods can lead to greatly increased blood sugar levels.  This article speaks of fast food, but I would imagine that a typical diner breakfast with sausage and/or bacon, fried eggs, etc. would be just as bad.

http://www.cbsnews.com/8301-504763_162-20049685-10391704.html

It helps burn fat, lowers risk of Type II diabetes, makes you smarter, and more!  Coffee truly is a magical beverage.  http://lifehacker.com/5986506/the-science-behind-coffee-and-why-its-actually-good-for-your-health

According to the International Coffee Organization, this year's harvest could suffer losses as high as 50% due to a blight on the coffee plants.  http://www.wired.com/wiredscience/2013/06/coffee-rust-epidemic/all/

Coffee linked to 50% reduction in risk of suicide: http://io9.com/coffee-drinking-linked-to-50-lower-risk-of-suicide-908280026