The final game I made for a jam day from my first game design class, with a theme of "Square". An arcadey, high-score game with gravity switching inspired by VVVVVV- which was a pain to program, changing the gravity also switched the momentum, which I then had to un-switch manually. You get two flips per jump, which can let you keep a ton of air time!

Rollin at 5 - electronic Kevin MacLeod (incompetech.com)
Licensed under Creative Commons: By Attribution 3.0 License
http://creativecommons.org/licenses/by/3.0/

Slight (or major depending how you look at it) visual inspiration from the game "Just Shapes and Beats". Check it out, it's cool.