I'll nominate a second license option: LGPL for all of Piper, specifying that Piper is a library and that all UI's and plugins/nodes are using Piper as such (a library). Jeff -- J.W. Bizzaro jeff at bioinformatics.org Director, Bioinformatics.org: The Open Lab http://bioinformatics.org/~jeff "Injustice anywhere is a threat to justice everywhere." -- Martin Luther King, Jr. --