Is there any existing web app that lets multiple users work with an interactive IDLE type session at once?

Something like:

IDLE 2.6.4
Morgan: >>> letters = list("abcdefg")
Morgan: >>> # now, how would you iterate over letters?
Jack: >>> for char in letters:
    print "char %s" % char


char a
char b
char c
char d
char e
char f
char g
Morgan: >>> # nice nice

If not, I would like to create one. Is there some module I can use that simulates an interactive session? I'd want an interface like this:

def class InteractiveSession():
    ''' An interactive Python session '''

    def putLine(line):
        ''' Evaluates line '''
        pass

    def outputLines():
        ''' A list of all lines that have been output by the session '''
        pass

    def currentVars():
        ''' A dictionary of currently defined variables and their values '''
        pass

(Although that last function would be more of an extra feature.)

To formulate my problem another way: I'd like to create a new front end for IDLE. How can I do this?