[toddynho]

I started BuySellAds (http://buysellads.com) while employed full-time at HubSpot (http://hubspot.com). A few years after leaving, my company ended up on the Inc 500 (http://www.inc.com/profile/buysellads) and we're still doing quite well.

- I had the project specifically spelled out in my employment agreement with them since I had already been working on it for a while. I started working for them because I genuinely believed in their mission, and there was a certain allure of a steady paycheck after freelancing for a while. I made the decision to leave after about a year of trying to juggle both.

- By the time I left HubSpot was 50 people and they had plenty of funding, so while perhaps they would have liked for me to stick around, there's nothing I did that has ultimately contributed to them becoming the billion dollar company they are today (a nice humbling lesson for the youngster I was back then...).

- I actually think doing this (as long as you can keep it clean legally and actually own what you're building in your spare time) far outweighs quitting your job before starting a company. I wrote a post on Quora about this in a little more detail (http://www.quora.com/I-plan-to-quit-my-job-at-a-software-com...)

[iambateman]

Oddly enough, in 2011 I was employed by BeaconAds, which licensed BuySellAds' technology, while I built a student news aggregator startup (I know, I know).

It didn't pan out very well.

[tehwebguy]

You gave it a shot and probably learned some things, don't feel too bad!