Missionaries in the work office

In the Savannah Morning News, Dana Clark writes an article named Missionaries in the office. The article describes how Danny Falligant, an attorney, sets up Bible study groups in workplaces.

Clarks says that "many people of faith turn to prayer and scripture whenever facing stress or frustration, even when that happens at work." These groups seem to thrive, some joke, when the stock market is down.

Another Savannah resident ,John Crosby runs a ministry called Priority Insight, "a local nonprofit organization and workplace ministry that helps businesses incorporate 'Biblical principles' at work. Crosby has worked with about 90 area businesses and is involved in about 40 local office-based Bible study groups."

Apparently, religious activities are legal in the workplace, so long as they are not mandatory.

So, what workplace rules do you have about religious things, written or unwritten? Could a workplace prayer or study group be started in your office?