Once you've used pipe2py to convert your Yahoo! Pipe into a local Python module, you can then host it as your own Google App Engine application. You just need a bit of boilerplate to handle the parameters and output formatting. I've created a sample project containing this boilerplate here: https://github.com/ggaughan/testpipe. You'll need to include a copy of pipe2py, so it can find the modules it needs, and replace the demo pipeline references with your own. See the README for details.