I've always enjoyed working at small companies. I've worked at larger companies which have the "level" concept of employees, it's kindda funny to me now :)

In my experience at smaller companies you get treated better, you are a more significant factor to the overall success of the company and there is very little corporate crap which often has silly requirements that get justified by a mystical word of being "professional", which often actually seems to achieve the opposite of treating adults as bunch of kids that need to be managed and controlled :)

Though I know it also can go very bad for people in small companies that have mini dictators in charge.