WOW those are amazing! I've never heard or seen one until I looked at that website. Very cool! I can't imagine one of those getting into a roll of nickels,but I guess anything is possible.
I took this photo from that website because I found a penny that had those ridges all around it and I thought what the heck is it and I threw it back and rolled it up. Are there hobo pennies too? lol I know it's still in one of the three boxes of pennies I was going to return to the bank tomorrow. I don't know if I want to go through all of them to find it though.
From what I understand these were first around during the 30s, when hobos during the depression would pass the time by carving Buff Nicks. I think some artists are more valuable. I also think there are people today making reproductions.
The cool thing about Hobo nickels is that some of the artists were so prolific that they have been able to trace some of them to the carver. Coin Prices had a good article about them in an issue from....last year I think. Could be wrong, I need to check my back issues.