How about an online daytimer/schedule for a small office that allows employees to book meetings and such. The employee would have the option of making it private or not. Then everyone in the office could see the schedule of everyone else's non private events. A table could be displayed to show who's in the office when during the day or week. The receptionist could then book meetings for the employees and the employee would be able to see it and the receptionist could also see the employee's.

You could also incorporate a message system and do do list or job list that everyone or certain employees could see.

I've been meaning to do this for my office, but just haven't got around to it yet. Always thought it would be a good idea. Don't know if it is too complicated for your project though.