If you're ok with kiting, a staff mesmer is... my god. I was soloing +2 elite-type mobs for skill point challenges. Condition spam feels really broken. I originally started out with a real heavy illusion clone/phantasm build, but while trying to level up all of my weapon skills for later I fell in love with the staff.
And Chaos Storm. Oh Chaos Storm, how I love thee. <3
So yeah, now I'm attempting a build that revolves around "Hey, how much can I horribly cripple the person I'm fighting? Let's find out!" As long as you keep an eye out and make sure enemies don't get the drop on you unexpectedly (a good rule for any class really), it's pretty nasty!