Software recommendations for projector titles/slides and simple visual effects at an event I'm looking for recommendations for software to use to run companion slides and visual effects on a projector screen at a public event.

Ideally, I'd like something that can:


Show titles/slides full-screen on an externally connected display
Show movies full-screen on demand
Show specific images on demand (i.e. 'go to John Doe's introductory slide', which I don't think a presentation tool like Keynote could achieve given its reliance on slide order)
Show simple visually interesting animated graphics - something to leave running while people are finding their seats.
Preferably be free or relatively cheap.


I considered Processing, but it seems a bit heavyweight for my needs. Keynote and PowerPoint are probably insufficient, given that I will need to jump around my different items quite a bit if the event order changes, and I can't really exit the presentation and click on a different slide while the event's running.

Thanks in advance for any recommendations.
You can do this in either Keynote or Powerpoint by building a simple menu system in a master slide. Simplest is to build a menu slide that will hold all the content you want to target and jump to. Then make a link back to this main menu slide on the master of all your slides. You can make it visible or quite small. Your choice. 

In Keynote the main menu slide is done via Insert > Text Hyperlink.
In Powerpoint you have far greater capability with macros, but can easily jump to a slide in the same way. 

I believe macros can be linked to text or graphics (button) where with Keynote, it's a text link.