random reply, here. if you're used to python, take a look at http://pyjs.org
your best bet is to use something like JSONRPCService to talk to a back-end server, which can be in anything, of course, as kakao says, and i'd recommend either django, or pylons. take a look at http://code.google.com/p/pyjamas/wiki/DjangoWithPyjamas
if you'd like to use django, or if you prefer to do your own stand-alone JSONRPCService, any of the suggested JSON RPC services mentioned in that page should be easily adatible as stand-alone and/or WSGI and/or as python CGI.