Strip all strings that exist in a MongoDB database. It will work recursively to strip **ALL** your strings. Binary data won't be affected.

strip_database.py

# -*- coding: utf-8; -*-

from bson import Binary
from pymongo import Connection
from pymongo.database import Database

db = Database(Connection(), "yourdb")

def _clean_dict(x):
    dic = {}

    def clean_elem(elem):
        if isinstance(elem, basestring) and not isinstance(elem, Binary):
            return elem.strip()

        if isinstance(elem, list):
            return map(clean_elem, elem)

        if isinstance(elem, dict):
            return _clean_dict(elem)

        return elem

    for key, value in x.items():
        dic[key] = clean_elem(value)

    return dic


count = 0
for col in db.collection_names():
    for doc in getattr(db, col).find({}):
        clean = _clean_dict(doc)

        if clean != doc:
            count += 1
            getattr(db, col).update({'_id': clean['_id']}, clean, multi=0)

print "%d documents changed." % count