Zak Boca and Dan Ushman, co-founders of the Chicago Web-hosting company SingleHop, had a lot in common growing up. They were both teenage entrepreneurs. (Boca is now 28; Ushman is a year younger.) They were both running online advertising companies in high school. They were both making good money doing it. And they were both looking for a friend. So it didn't particularly matter that they lived 450 miles apart.

Boca: It's a pretty geeky story. Dan and I first met, when we were about 12 years old, in this AOL programming chat room. Everyone had a screen name. Mine was Biz, and Dan's was CoderEggo.

Ushman: We'd prank each other, make programs to knock each other offline, and show off how skilled we were. We had a lot of fun.

Boca: Fast-forward four years, and we'd fallen out of touch but were both running our own online ad businesses in high school. By chance, we started e-mailing and referring business to one another, but we didn't recognize each other's real names. Neither one of us admitted we were 17, either.

Ushman: As we got more familiar, we came clean and realized we'd actually known each other years before. I remember I stopped feeling so alone. Throughout high school, we spoke daily but never made plans to meet until we launched our first Web-hosting company, MidPhase, in the beginning of college.

Boca: I didn't have any reservations about launching a company with someone I hadn't actually met. We knew each other so well already. We did all the planning over the phone, then, the day before we launched, in May 2003, I flew to Chicago from my home in Kentucky. Dan came to meet me at the airport. I got in the car, and he immediately said, "Wow, you are fat," then he turned on this hard-core Slipknot music and drove like a bat out of hell out of the parking lot. That night Dan's buddies came over and dragged us to some hookah bar, and I quickly realized Dan's a lot more laid back than I am, because all I could think was, we needed to get back to work.

Ushman: But that's why we complement each other so well. What I lack, Zak makes up, and vice versa.

Boca: We turned the website on, and, that day, we landed four customers. Within six months, we had 1,000. We both dropped out of school, and in January, I drove up to Chicago to open our first office, roaches and all. We grew MidPhase to $16 million in three years, but we were always itching to start something new, so we launched SingleHop in 2006 to serve larger clients. We sold MidPhase the next year.

Ushman: All along, I think what Zak and I have had going for us is, there's a lot of ingrained trust you get from knowing someone as long as we have.

Boca: It's true. So many partnerships suffer from trust issues, but that's not even a concern for either of us. We know each other better than just about anyone. We've grown up together.

Ushman: There are definitely times when I want to go out and do something on my own, but then I think about all we've been through, and I know there's no way in hell I could have done it without Zak.