Life is filled with people who sometimes could use a beating. But too few of them ever get it.

Here’s a story where it seems it happened. It’s a story about the uneasy co-existence of bikes and cars on Atlanta’s crowded roads. But this time, the tables got turned on the alleged bully.

Mike Smith is health care consultant who works with insurance companies. To burn off the stress and mind-numbing tedium that can sometimes come with that job, Smith likes to bike.

On Wednesday, the 47-year-old father of two rode from his Dunwoody home to meet up with a group of like-minded cyclists in the Vinings area for an evening group ride. These cyclists are a serious lot who peddle long distances on expensive rides wearing those tight little biking pants. But don’t hold that against them, they seem like nice enough fellows.

On his way home from the long ride, Smith was traversing a scenic and fancy stretch of Northside Drive in Sandy Springs just inside I-285 when, in his words, he got “buzzed” by a behemoth pickup truck. “Buzzed” in the parlance of guys with tight biking pants means the vehicle passed them going too fast and too close. Smith estimates it was less than a foot.

Post-buzz, Smith said, the truck stopped and an angry 6-foot-2, 210-pound fellow jumped out fuming and sputtering and cursing. The police report said the man promised that he was “going to #@&! you up!” Smith also recalls the guy told him, “It’s a bad day to run into me.”

Smith was terrified and disbelieving. Two days earlier in Atlanta, a man in a red SUV did a U-turn and ran over a cyclist after the two exchanged words. The cyclist in that case was still in intensive care Friday.

Smith said he did nothing to provoke the driver other than pedaling down the road.

At first, Smith tried to grab his phone and film the guy, because that has become the de facto human response to just about any event. However, there was no time, with a sputtering, angry motorist rushing toward him, so Smith grabbed his Colnago — that’s a fancy bike — and attempted to use it as a $10,000 shield.

He tossed the bike at the rushing driver, who by now had his hands up in a fighting position. The man slammed the bike to the ground and stomped it and then again turned his violent attentions toward Smith.

The man threw at least three punches into Smith’s head and body, the police report states.

“I’m backing up in retreat trying to get away,” Smith said, who had only been in one fight in his life.

The motorist threw another shot and missed. Smith (who is no little guy himself, maybe 6 feet and pushing 200 pounds) saw his spot and took it. He threw a straight left hand “square into his temple.” The physics involved with a straight punch into a rushing body create a reaction similar to a head-on collision. The man started falling as Smith delivered The Quietus, a second punch to make sure the man stayed put.

“He was down for like five minutes,” said Smith, with a hint of pride. He also grabbed the guy’s car keys to keep him from fleeing.

Police said the suspect had a scratch on his chin, “grass all over his back,” and told a story that “jumped all over the place and did not make any sense.”

It’s unclear whether this was because of the cans of beer he admitted drinking or Smith’s left hand, which was still swollen a bit as he reminisced Friday.

The 33-year-old Atlanta driver, who had a bad enough day without his name being printed here, was arrested and charged with simple battery and DUI. We can hope that he will cultivate a better attitude henceforth.

Dianne Thigpen, a passing motorist, watched the bizarre spectacle unfold. She called 911 and then went back to talk with Smith after things sorted themselves out.

“He was just defending himself,” said Thigpen, who sometimes thinks bicyclists irritate motorists by ignoring stop signs and street lights and putting everyone in danger. But, she thinks nothing of that sort happened in this case. In fact, all things point to Smith just heading home and minding his own business.

“He picked on the wrong guy,” Thigpen said. “Someone crazy like that can really hurt somebody. He was a pretty big guy. It was lucky he attacked a male with a big punch.”

On Friday, Smith was at home, still weirded out by his ordeal and getting ready to take his bike into the shop to see if the frame was damaged.

He, like several other cyclists I’ve interviewed this week, said getting buzzed or yelled at is nothing new. Sometimes, he said, “there’s not enough space for everybody. It creates conflict.”

But there is something motorists should remember: If you see a nerdy looking guy with tight pants and glasses riding a white Colnago, don’t mess with him! He has a helluva left hand.