A few years ago, I set aside my shock at how fast time had flown and went to my 20th college reunion at Fairfield University.

The trip changed my life because I reconnected with my college girlfriend, Karen. We hadn't seen each other in more than a decade, but things just clicked, and we got married less than a year later.

Now, I can't promise you'll rekindle an old flame, but I can tell you that truly great entrepreneurs will always find a way to attend their reunions.

Even if going makes you feel a little old, you'll always find something new to get excited about in that atmosphere. That's because reunions are full of opportunities for entrepreneurs. Here are a few of them.

1. New business ideas.

You'll have a conversation and suddenly you recognize new opportunity. That's what entrepreneurship is all about.

Jeremy Merrin graduated from Bronx High School of Science in New York City in 1976, and he ran into an old friend at his 25th reunion in 2001. They got to talking about food, and eventually she invited Merrin to taste some "real" Cuban food at her mother's house.

That dinner changed his life. He liked the food so much that he launched Havana Central, a chain of four successful Cuban restaurants with aspirations to become the "Cheesecake Factory of Cuban food."

"At a reunion, you automatically have a connection with these people even though you may not have seen them in years," Merrin said. "[They are] more likely help you than people you have never met before."

2. New clients.

You'll reconnect. You walk into reunion, see someone you haven't thought of in years, and 45 minutes pass without realizing it.

David W. McCombie III is a lawyer and former McKinsey & Co. consultant who now runs a private equity advisory firm in Miami. For him, a recent McKinsey reunion event proved to be a great call.

McCombie told me that while he enjoyed seeing old colleagues, it was his introduction to some older alumni that really paid off. Several of the conversations resulted in "actual client engagements," he said. "One in particular has become a very substantial client almost overnight."

He credits the setting and the sense of belonging with adding up to new opportunities.

"I actually have a similar story from my college reunion," he said, "where they also lump together classes in five year increments--allowing for great networking with older, more established professionals."

3. New chances to learn.

You'll suddenly realize that someone you knew years ago is now an expert in a field you want to learn about.

Entrepreneur Colin Grussing graduated from Yale University in 2007, and went to his 5-year reunion last summer. There, he ran into a college friend who now worked in media.

They got to talking about Grussing's various businesses--among them an online venture selling motorcycle sidecars, and another called RootSuit, specializing in those spandex coverall bodysuits that you see rabid fans wearing at sporting events.

We "went pretty in-depth about how the whole media system works," Grussing recalled.

Afterward, he thought about his friend's advice, and used it to pitch the television show Shark Tank. He made it on the show, and while it didn't lead to further investment, the experience raised RootSuit's profile and led to even more media opportunities.

4. New career opportunities.

You'll realize that you can help other people as well.

Logan Beam's story is a bit different. His mother graduated from high school in 1986, but she couldn't go to her 25th reunion two years ago because she and his father had just moved to Florida. So Beam, who was studying marketing and playing football at Wittenberg University at the time, went in her place.

"I wore a nametag with her maiden/high school name," he explained, and met many of her classmates.

Among them was Elizabeth Nickol, whose father and brother had founded All-American Clothing, an Ohio company specializing in 100-percent American-made goods. The conversation led to an interview, then an internship, and eventually a  job. Beam is now the company's director of marketing and communications.

"Working for and supporting 'USA-made' companies helps keep and create jobs right here in America. My job is to ultimately create American jobs. I really enjoy having that responsibility," he said.

5. New perspective on the choices you've made.

You'll have a conversation, or listen to what others have done since you left, and realize just how proud you should be of the path you've chosen.

Maybe you've put on a pound or two, or you notice some lines in your face that weren't there the last time you saw these people. Everybody else probably has, as well.

Statistics show that entrepreneurs generally have happier lives. You're an entrepreneur. Probably 90 percent of your old classmates aren't. You'll be happy you went.

Still, keep the gloating to yourself. You want to make sure you're invited to the next reunion, too.

A version of this article originally appeared in my column on Inc.com.