Unless it's either a huge complex app, a very CS heavy app or has some fundamental innovation you'll have huge trouble selling that code. Can you hit up some people that are interested in this space? Unless you can make that kind of an ad-hoc sale you'll be really lucky to get anything over 5-10k.
Open-sourcing is always one way to go about it. If you're determined going the 8-5 job route then maybe you're just better off trying to leverage this project/experience to get a great job?
And also if you already made up your mind about quitting then why not post it on HN here? That's one of the few potential places where someone might be interested in buying that.