Ditto on leaving the case plugged in otherwise its not grounded. ESD not not overhyped. I've screwed up memory and a LAN card before.
That sucks, maybe your an electric eel. It is overhyped, and you can consider it a fact

... I mean, you can argue it, which is fine. But you have to remember all of the computer MFG's that do hardware phone support that require you to replace a PSU, or Hard Drive, or memory over the phone... If, say for instance, you were correct, I doubt all of these companies would have an inexperienced end user working on the inside of a machine... But, I rest my case, because I have been there and walked people through working on machines that are sitting on carpet, unplugged from the back of the wall and fix the machines right over the phone. Does ESD claim the life of things? Never happened to me, nor anyone I know. Though even if a component did die, it would be hard to blame it on ESD with any absolute certainty.
Thanks for the input, though.
Edit **
Also, keep in mind that maybe you just do not know how to handle a computer part. Perhaps your hands were wet when you touched the memory... Maybe you still have chocolate on your shirt and it fell off on the cards gold contacts... Heck, maybe mini-me came in there and spit on your system. Just joking with this paragraph... But, you never know.
Edit 2 **
One more thing, I am not telling anyone here that they have to take my advise. They can choose to work on their PC any way they want. If you want to wear an anti-static band, that is great! If you don't want too? That is fine, I understand. You can do whatever you want with your computer. It isn't my place to tell you how to handle your computer parts and what to wear. *shrug*