I've only been happy at two jobs. At one, I shared an office with an awesome guy, and our personalities and senses of humor meshed well. We had a significant overlap in musical tastes, and enjoyed sharing music and witty banter throughout our days of work.
The other was a startup where five of us worked in an open room, regularly taking breaks for coffee and lunch together. We had a bat-shit insane CEO, which really gave us something to bond over. :-)
Looking at job postings is overwhelming. 50% claim a "work-life balance!" and a "work hard, play hard!" attitude, where I'm betting the work is harder than the play. The rest talk about "entrepreneurial spirit" and other codes long hours and isolation. It saddens me that listing hobbies and interests (more like passions) on a resume is considered unprofessional.
People are respectful with you need to get shit done but are also very social when you want. They also host a lot of events (at least one per week doing something - happy hour, game night, lunches, bowling, movies) which allow you to really meet the people working there if you want the social stuff. It's a great model to keep yourself not feeling isolated and productive.
But, of course, those periods never last forever. Eventually, the business changes, people come in or leave, and the company dies or takes another direction. The creative period may end suddenly, without ever resulting in a shipping product.
So the real issue - if you're looking to maximize "work happiness" - would be to find some heuristics at the resume or interview stage to determine who's actually got the mojo at any point in time. That, or find a way to constantly bring that spirit into a more independent business situation.