Clever solution regarding the sombrero one - it makes sense. No cigar though - let me clarify a couple of things.

The only information the prisoners can convey is a hat colour. The warden calls out "next", and the next person then shouts either 'black' or 'white'. No other words, no pauses, or they're fed to the prison dogs.

Regarding the queue, I don't think it really matters. But for the sake of argument let's say the Warden tells them where to stand.

Quote Originally Posted by Darkmatters View Post
Actually you did say they both took some time
Sure, but an unspecified amount. They mull it over to the best of their ability, that's all it means.

You're right the first guy could only know his if the other 2 are blue, so you can't eliminate all 3 being red until after the 2nd guy answers - I should have said the first guy proves the other 2 aren't both wearing blue and the second proves that there's only 1 blue fez in play.
I'm not convinced. How exactly does that follow? Couldn't person 1 and 2 both be wearing blue fezes? Then person 1 and person 2 would both see blue and red.

Also of course my answer depends on them knowing how many red and blue hats were in the box, which you never stated.
Naturally that's implicit. If they didn't know what was in the box it'd obviously be totally impossible.

Quote Originally Posted by Alyzarin View Post
My solution:

It was red. The first person would have to see either two reds or a red and a blue to not know his own color. But, the second person would hear this and be aware of what both the third and the first person were wearing. If the first person was blue and the first was blue, he was red. If the first was red and the third was blue, he would know that he would have to be red as well because otherwise the first person wouldn't have had to say I don't know. The second person only doesn't know if the first and third person are wearing red. This opens up the possibility that the first person either didn't know because of two reds OR a red on third and a blue on second, so he couldn't be sure about it. Therefore, the third person must know he's wearing red when the second person passes.
Nice job again! I'm not exactly sure what you mean by "opening up a possibility", but if you cut that out then the puzzle is basically done already - you've proven that the third man must be wearing a red hat.