The person that issues the 1099MISC is required to issue one if its over $600. They can issue them for any amount. You are required to report all income. If they sent that $100 1099MISC to you, they've also sent it to the IRS, they will be expecting to see it on your return.
♪♫•*¨*•.¸¸♥Lisa♥ ¸¸.•*¨*•♫♪