I've implemented initial support for "dropped spines". This is motivated by the ability to draw figures that look like http://jeb.biologists.org/cgi/content/full/211/3/341/FIG7 . I'm attaching the patches and an image created by the new example. This is a somewhat invasive change into the core of the axis rendering code, so I'm hereby requesting a review before committing it into the code base. In particular, I dropped the idea of using Traits in MPL not because I think it's a bad idea, but because that would involve more substantial changes. Anyhow, I'm attaching the proposed implementation as a series of patches. If the general form of this looks OK, I'd write up doc strings and a CHANGELOG entry and commit it. Should I wait until after the trunk release? Please let me know what you think. All the examples run with exaples/tests/backend_driver.py still seem to give OK results, and the test suite raises a few more failures, but these appear due to (sub)pixel shifts in text rendering rather than anything more severe. -Andrew