You introduce a gift bag. Two spectators join you and look inside the bag to see one hundred folded papers.
You explain that on each you've written a different movie.
 
You tip some out the bag and encourage the spectators to unfold as many as they like to check they are all different.
You can help the spectators if you like, or you can stand well back to ensure you don't do anything sneaky. It's up to you.
The spectators re-fold the the papers and place them back into the bag, giving the bag a quick shake to ensure the contents are mixed.
 
You instruct them to reach in and remove any paper and drop it on the table.
 
Perhaps the other spectator is invited to do the same so a couple of papers are in play for a more dramatic selection procedure.  
Either way, from one hundred options, one option is settled on.
Both spectators are happy that it is undeniably a free choice. 
They unfold the paper to see what they've chosen. 
You reveal your prediction to show you knew what they'd choose all along! 

Important Points:

- The bag is entirely un-gimmicked
- The spectators can look inside the bag at any point
- You do not touch the bag or papers during the selection procedure
- The spectator is the one who unfolds their choice
- Use as many papers as you like
- Works with Gift Bags, Paper Bags, Backpacks etc
- Can predict anything... movies, songs, celebrities, numbers etc
- Prediction can take any form you like
- Easy and reliable to perform