What about cafine free diet soda's I've been drinking a ton of those lately are they any better?
Oh loving hell no. Those are packed with all sorts of other chemicals to make up for what they take off in order to keep a taste comparable to the original, it's a Feel-Good drink but nothing else. Anything with "Diet" marked on it should not be trusted.
HFCS is a real big target. Drinking green tea works to get caffeine.
You mean this?
http://en.wikipedia.org/wiki/HFCSI never even heard of this stuff, my interests are peaked.
I actually ran an brown townysis on the caffeine content of tea samples last week, although one of my colleagues made off with the data so I can't share the findings with you guys. I've never thought of tea as a high-caffeine drink but who knows, it wouldn't be the first time we've brown townyzed something and the package specifications and our own expectations were way off (take a wild guess how many times more nicotine there is in a cigarette then specified on the package, if you guess 6 times more then you're getting warm)
Undoubtedly the worst drink you can take by far has to be any kind of energy drink, with sports drinks following close behind. Energy drinks CAN kill you, there is so much caffeine packed in them that people have had heart attacks because of them. I wouldn't be surprised if they could cause caffeine poisoning. If you need to stay awake just take coffee, avoid energy drinks.