Mmm that was... fun. Yeah.
Real quick, take a good look at this case:
(Bad picture, I know.)
Note every metal part in that, which is about 90% of the whole thing.
Now imagine all that metal conducting a large amount of electicity. Ah yes. Fun stuff.
So I'm aimlessly burning some cds on my computer, I pull one out, and rest my hand on top of my cd-rom drive. It was about this time that I noticed a slight tingling in my hand. A very PAINFUL tingling in my hand. At which point I swipe my other hand accross the tower out of reflex. Comp died, sparks flew, and I felt 400 watts of power coarse through my arms.
End result:
Yeeeaaah that hurt. Note the black on the bottom of my hand if you happened to miss that.
(Random here, but I definately need to do more stuff as cool as getting locked out of my house again. That was the best line of comments ever =D)