1. Popcorn: http://popopopcorn.com
2. Googolplex: http://www.googolplexwrittenout.com
10000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 PDFs and each volume contains 1000000 zeros of the googolplex number.
3. Pi Video: https://www.youtube.com/watch?v=NBKeK4_3_Hs
A youtube video that contains the first 100,000 digits of Pi.
4. Ptable: http://www.ptable.com/#Orbital
Fantastic online periodic table, clicking on the element opens the wikipedia page for that element.
5. Periodic Table of Periodic Tables: http://www.keaggy.com/periodictable/
Each cell links to a different way of organizing every type of atom in the known universe as well as other things like xbox games.
6. Freezeray: http://freezeray.com
Interactive animations that teaches us physics and some other things.
7. Phet: https://phet.colorado.edu/en/simulations/category/physics
Really similar to the one above.
8. Name that Charge: http://www.physicsclassroom.com/Physics-Interactives/Static-Electricity/Name-That-Charge/Name-That-Charge-Interactive
You'll be given a variety of situations where you have to determine the charge of the objects provided.
9. Gravity simulator: http://testtubegames.com/gravity.html
Select from stars, asteroids and planets, change their masses so you can see how they behave.
10. Physics Chemistry Interactive: http://www.physics-chemistry-interactive-flash-animation.com
This site allows you to play with states of matter, additive and subtractive color, prisms and more.
11. Frog Dissection: http://www.surgery-games.org/dissect-a-frog-2/
Take a trip to Biology 101 with none of the trauma that caused.
12. Falstad: http://falstad.com
Website full of physics applets.
13. Minute Labs: http://minutelabs.io
All the coolness of Minute Physics but interactive!