11 lines solution for https://www.thumbtack.com/engineering/pycon-2015/, based on https://gist.github.com/shayelkin/2397850f9b2c3df7e3aa (please excuse the golfing, I'm aiming for length)

thumbtack-golf.py

import operator, itertools
def inspiration(*nums):
    assert all(isinstance(x, int) and x > 0 for x in nums), "a deck of cards contains only integers"
    ops = {operator.add: '+', operator.sub: '-', operator.mul: '*', operator.div: '/'}
    possibilities = {reduce(lambda v, t: t[0](v,t[1]), zip(o, n[1:]), n[0]): (n, o) \
                     for n in itertools.permutations(nums[:-1]) for o in itertools.product(ops.keys(), repeat=len(nums)-2)}
    try:
        result_nums, result_ops = possibilities[nums[-1]]        
        return ' '.join('%s %s' % x for x in zip(result_nums, (ops[o] for o in result_ops))) + ' %s' % str(result_nums[-1])
    except KeyError:
        return None