sry

i have seen both of those but i have noticed they need a bit of tinkering before they are reliable.

The main reason most of these openings are not popular is because they are either unsound, out-dated (someone has come up with a refutation), or allow the opposing side to gain a significant positional or tactical advantage. The reason most GM players use the same openings over and over again is because they understand three things:

1. Memorizing hundreds of openings (or attempting to) will actually hurt your game in the long run. It is much better to master a few openings than to memorize many.

2. The openings they play are sound as a drum and are not easily refuted by the opposing side. They offer good middlegame and endgame chances.

3. They choose openings that are not only sound, but that they understand. You should play an opening not because it looks cool or because you can remember it easily, but because you understand the reasons for the various moves. They choose openings that suit their middlegame and endgame preferences, not those that are obscure or rediculous. (E.g. 1.e4 f4?!) 

For example: in the Nimzo-Indian Defence, Black attempts to stop White from building a large center. Here are the moves -

1.d4 (White opens with a move that announces his intentions of controling the center.)

1...Nf6 (Black intends to attack White's center with his pieces, and so makes a normal developing move.)

2.c4 (White quickly builds up his center.)

2...e6 (Not commiting to anything just yet, Black simply opens a diagonal for his Bishop.)

3.Nc3 (White intends a pawn-thrust to e4, but the pawn will need backup because of the Knight on f6.)

3...Bb4 (Black pins the Knight to his King, stops the center pawns from advancing, gets ready to castle, and is prepared to inflict doubled pawns on White.)

Now that you understand the moves, you should ask yourself: Is this the way I like to play? Do I want to trade my Bishop for his knight? Do I like the resulting position? Does this position conform to my playing style? If you can say yes to all these questions, then explore the opening further, master it, and put it to use in your games.

You should do this with virtually all the openings you choose. Research it a bit more, find out if there is any line in the opening that you feel refutes it. If there is, then choose another opening.

(P.S. 1.e4 e5 2.Ke2?! is absolutely ludicrous! I think I'll start using it...

Thankyou very much for the great post david you are totally right that we need to have all of these things in mind. Thankyou so much

anyone else?

The Nimzo-Larsen Attack and Owen's Defense are pretty underrated -- or at least undermentioned -- in my opinion, especially in using them to obtain the Hippo. Kingside-fianchetto (Hungarian, Modern, etc.) openings are mentioned much more often than the queenside-fianchetto ones.

the hippo is one of my faves :)

anyone else?

The Budapest!

i think the benko gambit is an underrated one. against the benko accepted, white gets a small material advantage, but black gets development and initiative, and against a strong opponent that can be deadly. if white declines, then black has the start of a queenside majority and can take advantage of that. white must play carefully...

Cordel Defense to the Ruy-Lopez

dont know about cordel but the benko is uber strong if accepted.

First: The Benko hardly seems underrated, isn't it a fairly common opening at the grandmaster level?

Second: I think the Nimzowitsch Defense is underrated (e4 Nc6). I used to think it was terrible and theory gave me that impression as well, but there's someone in my area who is about 1500 and gains consistent success with it. I've tried to prepare for it but I can only beat him as black (!!). By the way, 1500 may not seem incredible (I think average USCF rating is about 1450) but we are in middle school so he's doing great with it.

ok i have all the more reason 2 look into the benko thx

any one else got a good yet underrated opening?

I think the Nimzovich-Larsen is definitely up there. But, for success and obscurity try GM Michael Basmen, he's rated about 2600 and he uses 1. a3 2. h3. For something more sound, I'd have to say Nimzovich Defense (1. e4 Nc6). I went undefeated with it at a state competition.

Ooo coo; i will look into that nice job at states btw :)

g3 appears to be underrated by whoever made the ECO system. It doesn't seem fair that the Nimzo-Larsen attack (1. b3) gets its own ECO A01, yet Benko's (1. g3) gets stuffed into A00 with 13 other opening moves.

Very true.

OG 

I've toyed with it a bit, and it is certainly a lively opening.  I believe the Modern Benoni main line is on the theoretical skids at the moment, though -- the Taimanov variation (1.d4 Nf6 2.c4 c5 3.d5 e6 4.Nc3 exd5 5.cxd5 d6 6.e4 g6 7.f4 Bg7 8 Bb5+) has proven very strong in GM play, and no one has found a good rejoiner yet.

Of course, GM play is not the same as club play, and one could still get good results with the Benoni.  It's just hard to really take up something as your primary defense when you know there's a line your opponents can follow that will give them the advantage.