##Batch (24)
    msg/time:3 * hello world

Tested on Windows 7, but should work on any NT-based version of Windows, assuming you have MSG.EXE in your System32 folder. 

EDIT: Apparently MSG.EXE is not available by default on home versions of Windows. On Windows 7, for example, this is only available in the Ultimate or Business editions. However, you can copy the file over to your System32 folder and get it to work. (You must also copy over the appropriate MSG.EXE.MUI file to get proper error messages, but my "script" works without them.) 

You have to install software for most of these other responses to work, too, so I don't think that should be a disqualifier.