things I should play with and haven't:

new tool/paradigm
- m2ym/optima                       (pattern matching)
- lmj/lparallel/lfarm               (distribution/parallelizing)
- nikodemus/screamer                (constraint solving/logic)
- sellout/quid-pro-quo              (contracts)
- mikelevins/apis                   (message passing)
- rpav/conspack                     (event-loop-ish)
- danlentz/dstm-collections/ctrie   (functional collections/stm)

util/stdlib overhauls
- fukamachi/cl21
- mikelevins/folio2
- sellout/LOOM
- Kalimehtar/cl-std
- vseloved/rutils
- TBRSS/serapeum
- jmbr/incf-cl
- acorn/helpers

I also have a bunch of web framework/test framework/ORM type stuff but meh