I installed paper.js as a node module (have to npm install canvas first which requires the Cairo libraries) using:
dan@ubuntu:~/Desktop/papertest/node_modules/paper/examples/Node.js$ node AnimatedStar.js
/home/dan/Desktop/papertest/node_modules/paper/node.js/index.js:45
vm.runInContext(source, context, uri);
^
ReferenceError: self is not defined
at ../../lib/acorn-min.js:1:24949
at vm.createContext.include (/home/dan/Desktop/papertest/node_modules/paper/node.js/index.js:45:6)
at core/PaperScript.js:19:7
at vm.createContext.include (/home/dan/Desktop/papertest/node_modules/paper/node.js/index.js:45:6)
at new <anonymous> (paper.js:125:7)
at paper.js:32:13
at Context.vm.createContext.include (/home/dan/Desktop/papertest/node_modules/paper/node.js/index.js:45:6)
at Object.<anonymous> (/home/dan/Desktop/papertest/node_modules/paper/node.js/index.js:51:9)
at Module._compile (module.js:456:26)
at Object.Module._extensions..js (module.js:474:10)
This same error happens on both Ubuntu 13.04 (64-bit) and Windows 7 64-bit.