Spreadsheet-like expressiveness for CLOS, the Common Lisp Object System.
Please check out the Wiki for motivation and general overview: https://github.com/kennytilton/cells/wiki
No documentation other than the test suite, but ping me for help. I am starting on a port to Clojure called It's Alive! here: https://github.com/kennytilton/its-alive and that will be better documented.
It's Alive! is pretty far along and in some ways exceeds Cells in capability and even has a benign issue fixed.