I really liked the "Balcony" idea you guys are talking ab out on the posts above. I would really like to see a card like that. If it existed, it would bring a new age to Throne Room-based engines. Perhaps, the discard afterwards is what makes this card practically unplayable. I have thought of a version that, perhaps, could have been better for this card:
Balcony
Cost: $5
+2 Cards
Choose an action card in your hand. Play it twice. If you do, trash a card from your hand.
I'm pretty sure, though, that Donald has already thought of various versions for this card that couldn't make it to an expansion set, but i believe that this version is not really catastrophic. It requires a card to be trashed, so you need to have junk in your deck in order to make it work and you are also forced to "throne" a card, rather than allowed, as it is with Throne Room. Additionally, the "If you do" statement does not let the card be used as a "free" trasher.
Another version of this card that i have thought, is to cost $3 or $4 and either trash the Balcony played, or trash the action throned.