Damiano's Defence. 1.e4 e5 2.Nf3 f6.
Worst Chess Opening

There is nothing wrong with a3 since it's so useless that it's like you're playing black with the preventive a3 in. It can also suprise people and make them convinced they have to refute it but it's no worse than playing black. Of course I don't think it's correct to always want to be black.

1.h4,followed by 2.a4
Formation: Hippopotamus Attack
These are white's. now blacks:
Borg Defense; 2...h6
1.e4 f6 2.d4 g5 3.Qh5#

Na3, the sodium attack
The better pun would be Nh3, the ammonium opening.
Nh3 is ammonia, not ammonium.
Ammonium is a move that requires the opposing king to be on g1, f2, f4 or g5:
Nh4+

Na3, the sodium attack
The better pun would be Nh3, the ammonium opening.
Nh3 is ammonia, not ammonium.
Ammonium is a move that requires the opposing king to be on g1, f2, f4 or g5:
Nh4+
Uh, that's what I meant.

I think 1.g4 is the worst of all 'legit' openings. Here is what was said about it by Horowitz (1964) in Chess Theory, Opening and Practice:
"a defiant almost contemptuous beginning as though to show White can get away with anything on his first move including this self inflicted wound. ... White appears to be saying, "I can toy with you....and you are impotent to extract a penalty""
And he goes on to offer further opinion on The "Spike." p. 781
I don't know what you're talking about -- everybody loves the Grob.
What is the WORST chess opening???