Found this thing earlier today. 192 UN states in 10 minutes. I got 84 down, 104 to go. 44% is pretty miserable, I think.
How did you do?
I got all but about 20. I proceeded by geographic area.
I can name EVERY ONE listed in “Yakko’s World”. (I spent quite some time learning the song.) While not entirely accurate, it’s close enough for me. And mildly amusing/impressive to whip out on the rare occasion that it’s appropriate.
Only 102. 
But I didn’t forget Poland!
Only 88.
Afghanistan, Albania, Algeria, Argentina, Australia,
Austria, Bahrain, Belgium, Bosnia and Herzegovina, Brazil,
Canada, Chad, Chile, China, Colombia,
Costa Rica, Cuba, Czech Republic, Denmark, Egypt,
Eritrea, Estonia, Ethiopia, France, Germany,
Greece, Guatemala, Honduras, Hungary, Iceland,
India, Indonesia, Iran, Iraq, Ireland,
Israel, Italy, Japan, Jordan, Kazakhstan,
Kenya, Latvia, Lesotho, Liberia, Libya,
Lithuania, Luxembourg, Malaysia, Mexico, Montenegro,
Morocco, Mozambique, Nepal, Netherlands, Nicaragua,
Niger, Nigeria, North Korea, Norway, Pakistan,
Papua New Guinea, Paraguay, Philippines, Poland, Portugal,
Romania, Russia, Saudi Arabia, Serbia, South Africa,
South Korea, Spain, Sudan, Sweden, Switzerland,
Syria, Thailand, The Bahamas, Turkey, Ukraine,
United Arab Emirates, United Kingdom, United States, Uruguay, Vietnam,
Yemen, Zambia, Zimbabwe.
Damn.
You might want to check your math, too.
I’m so good at geography, but after 7 minutes and only guessing 80-something countries I got so frustrated that I gave up. I used to be a webmaster for MUN! I used to take quizzes matching capitals to nations and nations to continents for fun in my spare time! I was thoroughly disappointed in myself. Of course, spelling Liechtenstein took me three tries, but I’m amazed at all the ones I missed. Gah!
Aw, I was so coming in here to post that. One of the most useful things to memorize.
I got 97 of them. North and South America and western Europe weren’t much trouble, but the former Soviet republics and Africa gave me fits.
I should also note that for some reason I thought it was from the list of EU countries at first, so instead of racking up easy points on geography I tried to remember all of the countries currently in the qualifying stages for UEFA 2008. Which is clearly not the angle to start at. It was when I saw the “192” that I realized I’d made a mistake.
Sorry, I need one that’s not going to give me flak if I write Camboya, Afganistán and Ceilán. I can write those in English if I have time to think… but I need to think about “where the heck does Afganistán have an h in English”.
I only got 78. I know more countries than that, but I choked on the time limit. I at least named a few in every continent.
I got 116. I think this thing is unfairly biased against bad spellers. Who the hell can spell Herzegovina, Kyrgyzstan, and Liechtenstein? I tried each spelled several ways without luck. I honestly don’t know how I got Azerbaijan on the first try. Also I tried to spell some of those saintly islands with “St.”, but I guess they only accept “Saint”.
I named 60 and just completely blanked out. Had plenty of time left, but just didn’t have anything upstairs.
To be fair though, I actually thought of Liechtenstein and Luxembourg but couldn’t spell either one right.
I managed to get 99. I’m a slow typist and I’m sticking to my excuses. 
I got 67, according to the scoring. If I could SPELL better, it would have been the 70s. Leichtenstein, Bosnia and Herzegovina, Ecuador, Dominican Republic (that one I have no clue HOW I managed to spell it wrong…), Papua New Guinea (forgot the Papua)…then there’s the ones I knew but didn’t get because I spent so much time working on the spellings of them, and Colombia (I kept trying to spell it with a u… >_<), the Netherlands (started with Holland, then The Netherlands, finally succeeded on Netherlands), Kazakhstan, Vietnam and Turkmenistan…
I tried to use Wakko’s World, but I blanked after Peru.
They’ve pretty much all been named by now, haven’t they?
I got 93, 99 to go. Man alive, I suck at the central African countries.
Oh yeah, and the spelling and “exact name” bit that others have mentioned.[spoiler]I tried Great Britain, Britain and (in a moment of desperation) England, but United Kingdom just didn’t pop into my head. I tried US, USA, United States of America and just America, but no dice. I didn’t even try United States, which is what they wanted, as several countries are United States of Something. I knew Saint Kitts and Nevis but spelt it St instead of Saint, the only way I’ve ever seen it spelt. I tried Tchad and when I missed I assumed they weren’t in the UN; I didn’t remember that it’s spelt without a T in English. Oh, and “the” Bahamas? “Democratic Republic of the” Congo? Naah, we all deserve a higher score here.
Having said that, how the flying buttered-up Kermit did I manage to forget Hungary?[/spoiler]
I got in the high 80s, but also had trouble with spellings. It took me several tries to get the USA the way that they wanted. I left off Switzerland since it’s not a member of the UN, so I get marks off for lack of reading comprehension. I could not remember how to spell Vanuatu, for example. If I had treated this like an SAT test I would have just skipped by that rather than trying to re-spell it several times.
I got 147, although I think it should be 149, since I gave up on trying to guess the exact names after “Congo” and “Bosnia-Herzegovina” failed to work.