After some deliberation I decided that it would be both fun and intuitive if pickupable objects like barrels would bounce on springs. In theory this would have been a easy thing to achieve but theory isn't worth much when it comes to actual, hands-on gamedev. And so it happened that I needed 3 tries to get this working the way it was supposed to.

"I have to go, my planet needs me" -Barrel, probably

The first attempt was...fascinating. As you can see, I forgot to set the spring as immovable, which resulted in this incredible display of aerial splendor. Things got more grounded after I stapled the spring to the ground:

Barrel sees ya, Barrel don't care.

Annoyed at having been robbed of the ability to fly, the barrel just decided to sit there sulking. In actuality of course it was due to the collision code: While the collision was working (as you can tell from the spring freaking out) any velocity the spring gave the barrel was cancelled due to the collision code trying to separate the two objects in a calm and orderly manner. So finally, after one last fix...

...we got a bouncy barrel! Now you can get objects to even more places to try and break my carefully designed levels.