You can put a PowerPoint presentation on almost any mobile device including your iPod.
Provided your mobile device supports JPEG format images – most will – open your presentation in PowerPoint and choose File, Save As and select the JPEG format, choose All Slides and PowerPoint will save the slides as JPEG format files that you can now upload to your mobile device as you do any other photos.
If your mobile lets you play images as a slideshow – voila! PowerPoint to go!