i vote 1... d5: the Scandinavian
What Do You Think Is Best After 1.e4 For Black? Vote!

If white can play 1.e5, I say just go ahead and castle.
Na, that drops a knight and bishop.
What about 1...dxe4 e.p.?

I've never seen that before but the fact that c6 has to be played I would say means you don't have enough tempo for the pawn. I would bet it fares very badly for black.

Black has the position white would start with if white started with 7 pawns. Any decent gambit is AFAIK a tempo up on that one.

i like it, but i dont play it in real-life tourneys because it is too risky. I use it in bullet games

OT but worth study, due to the suddenly discovered possibility in this thread of 1.e5:
If you want some really cool replies to 1.d4 , play this one through (posted today in this thread).
White however manages to find equally creative replies; I particularly admire his moves 7, 13 and 14. Black even refuses to move for 3 moves or so, but comes bouncing back. His 6th move is particularly resourceful.Play it through slowly and enjoy! (and no, it wasn´t my game unfortunately)

oops! the title is supposed to say 1.e4! sorry! because of this, does anyone want to change their vote?
1... e5: 9 votes
1... d5: 2 votes
1...e6 2 votes
1...c5: 14 votes
1...f5: 1 vote
1...Nf6: 2 votes
1...c6: 3 votes
1...d6: 1 vote
1...f6: 2 votes
I will add more when people suggest them. You don't just have to pick 1... e5 or 1... d5, you can pick anything.
Voting ends on Christmas! (i know, long time)