Depending on the definition of the word startup, most (if not all) successful open source communities started off as a toy. The Ethereum foundation is a recent

Depending on the definition of the word startup, most (if not all) successful open source communities started off as a toy. The Ethereum foundation is a recent example of this. I also personally think that "toys" are great for building and sharpening one's skills, much like Lego in the real world. This can be everything from you trying to "sell" your toy so other kids will come play with it, all the way up to learning how to glue software components together and make it work. Some technical toy projects have steep learning curves, and as an engineer myself, I see it as an opportunity to learn things I otherwise wouldn't working on a "serious project".