WinNuke client for iPhone
Nuker is a vulnerability testing tool that checks a local Windows XP machine over the network to ensure it is not open to an RPC Denial of Service attack.
Only Windows XP machines running the initial release of XP and early releases of Service Pack 1 are affected, and if your local machine is affected it is a *very* good idea to update it by running Windows Update.
If the target machine is vulnerable, it will display a warning dialogue and shut down after 60 seconds with notifications onscreen.
Here is a demonstration video.