Ha ha, Instant Arcane Explosion is the best mage spell in the game.
Me and Redjake were taking on twenty 40 elites simultaneously in Razorfen Downs with it. I would spend 4000 mana on flash heals and he would spend 6100 mana on Arcane Explosion. After 20 seconds, you have twenty dead 40 elites and a ton of money/EXP.
I believe you 100% Ever. There are really easy ways to make money in this game that some people won't accept. I won't mention them here but it's quite obvious. If I hadn't bought every single blue item that my priest and warrior could use up until now, I'd easily have 90g by my midthirties. Hell, it'd probably be way over 100, maybe closer to 200g. That's why when I got to level 32 or so on my priest and warrior I wasn't really concerned with getting mount money. One economy in the game is a gauranteed money maker...has been since closed beta.
-Lasereth