What open source project is complete and doesn't need any help? Besides Go or PHP and Github, you've told us no preferences, so it's kind of open ended. What has you motivated, what are you looking for? Would you mind spending four days adding a basic feature in a relatively unfamiliar language?

I've recently contributed to an opensource project myself for the first time. The project is Filezilla (the client in particular), and I added a feature to create a new, empty file on the server. About 70 lines of code in the end, but having little c++ experience it cost me two evenings, though that includes getting it to compile (also a first, compiling a project with a number of dependencies and lots of code on Linux). The patch is being reviewed now, and I have good hope it makes it to the next release. It feels really good to complete because I've actually done something measurable; solved a problem in software used by thousands.

I'd like to take such a project on again. It was small enough for me to grasp in a language that I was not very familiar with, and I learned lots of things. And it solved an actual problem. So those are things I'd be looking for in a project to take on. Perhaps you prefer something bigger? Or not? Not that I'd know a project to suggest, but perhaps others do ;)