If a gambit early on is unsound, just look a few moves deeper and inevitably there's a sound one deep enough in, very often based on a similar idea.
Gambit Openings

1..f5 after 1.Nf3 is probably at best an inaccuracy if not a mistake because of 2.d3 Nf6 3.e4, which is the gambit I assume optimissed is talking about.

That does not refute the Dutch reti at all, considering white barely has any advantage in that line.

That does not refute the Dutch reti at all, considering white barely has any advantage in that line.
I didn't say it refuted it, but I did say it was at least an inaccuracy to play 1..f5.
I haven't played the Reti for a long while, so I am not so familiar with the line anymore, although I have access to some analysis and I believe it does lead to a sizeable advantage.
What second move would you play as black after 1.Nf3 f5 2.d3, I'll give you my line.

Try Tennison counter gambit against center counter defence.
1.e4 d5 2.Nf3!?
Also you may find Budapest Gambit interesting. I heard it was used in a super tournament to win against Gelfand or someone but I didnt check the news properly.
1.d4 Nf6 2.c4 e5!?

You might also enjpy this disscussion on agreessive openings in another forum.
http://www.chess.com/forum/view/chess-openings/aggressive-openings2

That does not refute the Dutch reti at all, considering white barely has any advantage in that line.
I didn't say it refuted it, but I did say it was at least an inaccuracy to play 1..f5.
I haven't played the Reti for a long while, so I am not so familiar with the line anymore, although I have access to some analysis and I believe it does lead to a sizeable advantage.
What second move would you play as black after 1.Nf3 f5 2.d3, I'll give you my line.
Probably just Nf6..

Budapest Gambit is just another opening since its not a true Gambit, although its perfectly playable..I mean black can't keep the pawn can he?

Kings Gambit less sound than Danish?? How..? I'm not talking about crazy stuff like the Muzio but just standard sacrificing a pawn for an attack Kings Gambit. The Danish is dangerous especially in a low time control game or blitz but the compensation and attack doesn't seem as forceful as the King's Gambit mating attacks.

As I recall, they transpose only if White knows his theory (5...b5 6 Bf1 Nd4 7 c3 etc. 5...Nd4 6 c3 b5 7 Bf1 etc.)
The Dutch isn't a mistake, I love the Dutch...