I've not worked in a company(i'm a student), but since i have been doing some collaboration with people(for projects and papers), i've noticed that one of the most, if not the most, important thing for every group of people is communication.
I'm a computer programmer and therefore i'm wondering whether creating software that manages communication between companies departments is a good idea, and how it can be extended to solve people's problems in a company.
Moreover, what would you think is a promising field for a startup software to aim for ? What would be a key component that companies need nowadays but is not sufficiently provided ? Or at least not in the manner that companies would want it.
You have many questions here, so I will restrict myself to answering the first.
I believe that the coffee cup is a far better tool for improving communication between departments in a company. People should walk around with their coffee cups and talk to eachother. A computer system can be used to facilitate communication over distances, across time (asynchronous), to restrict it to reduce errors or standardize it to improve efficiency and so on, but to create understanding between people, the coffee cup is far better.