There's a Demigod: Day 1 Status Report we missed between the day 0 update and the day 2 report with some details on how much piracy they saw after the street date was broken for Gas Powered Games' action/strategy game, which has no DRM protection (thanks GamesIndustry.biz). Some of the issues related to an influx of unauthorized users have been addressed, but the ratio of stolen to legitimate copies is pretty startling:

The system works pretty well if you have a few thousand people online at once. The system works…less well if there are tens of thousands of people online at once. And if there are over 100,000 people, well, you get horrific results such as the game being incredibly unresponsive due to simple web service calls that were considered pretty benign during the beta that suddenly start to bring down firewalls and such due to the sheer massive number of calls that are being made.

Sadly, most of the ~120,000 connections are not customers but via warez. About 18,000 are legitimate. So anyway, we spent a lot of time today trying to isolate out the warez users from the legitimate users (it would require a lot of surgery to actually break them and even if we did, there’d be no friendly “ha ha pirate” message which would result in people just saying the game is buggy). Mind you, the game makes relatively few server calls, it’s just the sheer number of people.