The gravity of this work is laughable :)

Here are some fun examples of humorous gravity-themed artwork from Chinese artist Li Wei.
The interplay between gravity/seriousness and physical weight/emotional weightlessness (i.e. humor) is fun and interesting. There's nothing I can find that says how the artist creates these works, but it's a likely guess that there's some Photoshop or other computer manipulation going around.

They remind me a lot of Eric's Umbrella PSA series :)  Be sure to use gravity safely now, everyone!