I started to create a collection of microbenchmarks for CPython from scripts found on the bug tracker: https://github.com/haypo/pymicrobench
I'm not sure that this collection is used yet, but some of you may want to take a look :-)
I know that some people have random microbenchmarks in a local directory. Maybe you want to share them?
I don't really care to sort them or group them. My plan is first to populate the repository, and later see what to do with it :-)