Things like varying overtime rates depending on time of day, accumulated hours, whether it's a holiday, different rates for depending on specific work assignments, etc. It's not as simple as a flat rate x number of hours. But it's nothing that hasn't been done before, either.
Agreed. You also have to think about who can approve the hours booked. So you would need to have some sort of hook into the HR / Org database which determines each users entitlements. It gets very very complicated! Technically, the problem is nothing new. The difficulty lies in designing the system and getting it to work correctly with an organizations existing business processes and systems.
In this case, one of the issues was that worker's were incensed over biometric scanners proposed for the system intended to fight pervasive time reporting fraud.
The City of New York employs about a quarter of a million people, which is around the same size as General Electric or GM, worldwide, performing a wide range of job functions.
Also: the particular system under development included hand scanners, so you should include developing for that.
