It's from this artist UncleBibby: http://freemusicarchive.org/music/UncleBibby/Free_Music_Project_Vol_1/TheSpidrmans. He's got a lot of other free music too.
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If you don't fix the wall progress currently going on, people will stop playing. There aren't really a lot of things to do on this idle, and even reseting won't make any good at this point. I friendly suggest you to take some serious actions towards this, for the sake of the game popularity.
"You saved up $100,000,000! That's a lot of nickels" and "You've earned $100,000,000 over the course of your carrers!" are swapped. The first appeared when I had about 90,000,000 and the latter when I'd saved up the sum of 100,000,000.
 "Wondrous Lands"){kind=icon}
 "Dogs Vs Homework"){kind=icon}
 "Music Catch"){kind=icon}
 "Home Story: 1971"){kind=icon}
 "Animation Throwdown"){kind=icon}
 "Use Boxmen"){kind=icon}
 "Cube Escape: Birthday"){kind=icon}
 "Crush Crush"){kind=icon}
 "Winner Pet"){kind=icon}
 "Black Sun"){kind=icon}
 "Solomon Circle"){kind=icon}
It's from this artist UncleBibby: http://freemusicarchive.org/music/UncleBibby/Free_Music_Project_Vol_1/TheSpidrmans. He's got a lot of other free music too.