Personally, I find I learn more when I use tools to solve problems I haven't tackled before. Perhaps you should look at the work you do and the tools you use to do it. Perhaps you'll identify a problem you can tackle.

Barring that, perhaps you can think of a project that you have wanted to attempt and then give it a whirl.

Perhaps you can think of a module you've always wanted to have.

Perhaps there's a project you've always wanted to redo.

Inspiration can come from many places; you just have to be open to hearing the voice urging you to take a crack at something.

As always, YMMV...

--f