[Changaco]

As others have pointed out, platforms to fund work on open source projects already exist, and the best part is: they're open source themselves, so you can contribute! In fact I was the top developer of Gratipay for a year myself, and now I've created a fork called Liberapay (the reasons were the legal difficulties Gratipay faced in the US, and the decision its founder made to turn it into a non-neutral platform).

Links:

https://liberapay.com/ https://github.com/liberapay/liberapay.com (Python)

https://gratipay.com/ https://github.com/gratipay/gratipay.com (Python)

https://salt.bountysource.com/ https://github.com/bountysource/core (Ruby)

https://snowdrift.coop/ (not operational) https://git.snowdrift.coop/sd/snowdrift (Haskell)

[whit537]

There's also https://opencollective.com/ https://github.com/OpenCollective/OpenCollective (JavaScript).

[vijayr]

Are there collaborative translation services for open source apps and products? One could of course use google translate, but it would be nice if the translation is done by humans who actually use the product/service they are translating.

[Changaco]

Liberapay uses Weblate: https://hosted.weblate.org/projects/liberapay/core/

Gratipay uses Transifex: https://www.transifex.com/gratipay/gratipay/

[ygjb]

In addition to the others listed, there is also https://crowdin.com