I've done it... I've descended into madness. I've created my first World of Warcraft mod. It's called Gyro, short for Get Your Raid On. It sits lurking in the background, waiting until you join or leave a raid, and then it springs into action, executing a predefined macro of commands. I use it to switch my UI around depending on whether I'm in a raid or not. (I don't need to know my mana regeneration rate and my threat level when I'm walking around town.) But, I suppose you could customize it to just /yell "For the Horde!" every time you join a raid too.
Debugging sucks, though. It's the typical Neanderthal style of debugging—make changes, reload everything, try it out, observe problems, and repeat. Then again, I wasn't really expecting to be able to attach Visual Studio to the thing.
So, that was fun. I had a good time getting my feet wet, so I think that sometime in the future, I'll try my hand at something a little more complicated (and useful). I've already got the basic idea planned out...