Back in the arcade days:
MK1 - not too big here, just an 18 streak. All the players here were very good. So many fights over this game. One time I was playing the computer and a guy had his quarter up so he could play "the cpu" next lol (he didn't want to play me because he sucked), some other kid walks into the 7-11 and sees that nobody is playing me and puts his quarter in and starts playing me...the guy with his quarter up is secretly getting pissed and reaches ACROSS me and punches the guy in the face LOL and starts yelling at him, wow crazy shit. I kept on playing lol
MKII - several 50 streaks and one that was around 210. When MKII 2.1 came out, our arcade had SEVEN machines next to each other with about 50 people crowded around at all times and I was there from open to close. There were guys that would play all day just to try to beat me, when they weren't playing they would gather together and discuss how they think they should play me next time lol ...on the PS3, I got my 50 streak once but now nobody lets you maintain a streak, they let the timer run out.
U/MK3 - way too good of comp where I played to get any long streaks, I think I had a 12 streak once.
MK4 - 82 streak - all the good comp stopped playing, and I had to actually travel the state to find comp. They still sucked.