I'm not convinced this is such a great combo, chwhite.
First of all it requires a +2 action card, a golem, or a double throne room/ KC. So there is no fundamental synergy here, but there are certainly plenty of situations where you could set this up.
Fortune Teller on its own is actually a decent attack, it really can slow down your opponent when you need it most.
Jester, however, is more of an offensive card, more like a Smugglers. If your opponent draws a copper, you can give him another, but that is just a consolation prize... neither the new copper nor the old one go back on top of his deck. It's nice to have him draw a victory card because Jester causes him to gain a curse, but it's a much weaker curse than a Witch's curse because it gets rid of that terrible card from his deck and improves his next hand.
Together you have a double-terminal combo that results in a reasonably mild attack when you finally set it up. If they randomly come up together with a +2 action card, sure, play this combo. If you have to go out of your way to buy either one of these cards, it's probably not worth it.
Fortune Teller/ Saboteur is a pretty solid late game gambit though...