The only thing better than bubbles is more bubbles (according to most children). To maximize your bubble output, you're going to need the “Bubble Bucket” created by Thingiverse member Scratchhax.

Working like a conveyor belt of fun, the machine uses a collection of bubble wands woven together. They circle through a bucket of soap and a fan blows the bubbles into the sky. This is great for people who need a lot of bubbles but don't want to work for them.

[h/t: Laughing Squid]