While looking up information for the national anthem of one of the countries at the Olympics, I discovered:

The longest national anthem, lyrics-wise, is Greece, with 158 verses.
The longest national anthem, music-wise, is Uruguay, with 105 measures.
The shortest national anthem is Uganda, with eight measures.

Other national anthem facts:

http://www.national-anthems.org/facts.htm

Funniest bit of trivia:

The music blared at a soccer match in Athens between China and Greece, and the crowd rose and stood in respectful silence. They assumed it was the Chinese National Anthem. The Chinese players also stood to attention, thinking it was the Greek National Anthem. It turned out to be a toothpaste commercial...

I realize that the playing of our National Anthem at the Olympics isn't meant to be a concert, but the rendition that was chosen for this Olympics is less than stirring, IMO.

Many South American countries have a long version and short version of the anthem. At sundown the ship would play the US anthem over the loud ststem and the guest countries. I think it was in Columbia they played the long parade version and we stood on the pier over five minutes while it played. Our goal was to out of hearing before the music started.

One of the US athletes who received the gold medal, started singing the national anthem, turned to her fellow US athlete who won the silver, and mouthed the words, "This is really HIGH!" It is an unusually high arrangement.