clive
I started clive at the start of this year. It allows you to livecode JACK DSP process callbacks, providing not much more than an automatic C code recompile, reload and state preservation.
I've performed with it 3 times so far, the last in Paris but that isn't online yet. Here are two sets from February in Amsterdam, available on the Internet Archive:
The code is available here:
git clone http://code.mathr.co.uk/clive.git
Or browse clive on Gitorious clive on code.mathr.co.uk.