a game
Ponziani Opening

http://www.chessgames.com/perl/chessgame?gid=1128295 This is a game played by Spassky ( black ) in the ponziani counter gambit but his opponent played 4 d4 instead of 4 exf5 . My database indicates that 4 d4 is best and scores much better than 4 exf5 .

Reb, fortunately databases can't play chess and are very often wrong. Another classic example is in a main line of the Anti-Moscow gambit where the most common move for Black is h6- h5 which is practically losing, Nbd7 or Rg8 must be played according to CCGM Tansel Turgut

Reb, one thing I know for sure is that after 3. c3 f5 4. exf5 is the best move for White and is very strong.

Firebrand, thanks. Yes, those look like good developing moves. Pulled my Q out too soon. Was wondering, should i not even have moved my light squared bishop to b5? Course if he pulls his 2 pawns out to shoo it away, and my light sqr bishop ends up on b3, is that a bad thing?
I like that game LastStraw...will have to learn it. Black's devel. is nowhere no and will surely lose his N in the corner at some point.

10.h4 g4 11.Ne5 if I'm not mistaken Firebrand. Turgut is the highest rated ICCF player in the US I believe, though he plays for Turkey

You are right Dave 4.ef5 is very strong and after 4... e4 we are playing Nd4 and d3. Almost a clear advantage for white
What does White play on 4...d5?

5 Bb5 this already a clear advantage for white. See Horwitz Harrawitz 1846!
There is some good analysis in Dave's book on Ponziani
Yes, I've seen that game. 7.Ne5! looks like a dangerous improvement on that game, but Black seems to be ok after the Schliemann-esque 5...Qd6!?

We ran the variation with 3. c3 f5 4. exf5 d5 5. Bb5 in a chess engine vs chess engine tournament and White won all or most of the games. Here is one Equinox vs Viruivius

Firebrand. I will have to admit to not hardly considering 3. c3 f5
4. exf5 Qf6 and your equalizing lines are interesting.
I will suggest 5. Bb5 is at least worth a look.
Also, this line which is a continuation of your analysis [I do not know if it is reasonable or not as 1 hour not long to analyze]

ponz111, here is a question for you. If one were to become a ponziani player, the opening only works with 1...e5. Do you have a similar variation against the sicilian, or do you just play standard sicilian lines?

The Ponziani only works against 1. e4
Against the Sicilian I play 1. e4 c5 2. Nf3 d6 3. Bb5+
or 1. e4 c5 2. Nf3 Nc6 3. Bb5
or 1. e4 c5 2. Nf3 e6 3. d3
or 1. e4 c5 2. Nf3 d6 3. Bb5+ Nc6 4. Bxc6+
At least when I was playing 15 minute games...
The closest Sicilian line to the Ponziani would be
1. e4 c5 2. Nf3 Nc6 3. c3
Kantifields did you see that move [Ng1] in a game or in a variation being examined?