There's another: too much caffeine raises cortisol levels which can interfere with sleep quality
It's also not super great for your heart (not saying it's TERRIBLE, but it will raise your BP/pulse rate a bit), and it's diuretic effects can indirectly dehydrate you, as well, which will increase blood sugar.
And the diuretic effects can damage your kidneys. Ask me how I know. ;(
Oh, and NSAIDS can also damage your kidneys.
If you take too many NSAIDS and you also drink too much coffee, you can get a nice little double-whammy.
I wish I could gain a tolerance for caffeine. Getting a coffee at a cafe is such a nice experience but I end up getting panic attacks from too much of caffeine.
The worst part about caffeine induced panic attacks for me is the unpredictability. I can drink a Coke/Pepsi or two occasionally with no problems, but I had a sweet tea this afternoon and am now completely jittery.