Yes, it can be done! There are at least seven ways you can sleep absolutely for free. And the best news: none of them involves park benches or sneaking out of hotel windows via the fire escape at 4am.
My favorite? It also happen to be one of the easiest: Couchsurfing. This freebie version of the old hosptiality network model allows you crash on a couch or spare bed in a friendly local's apartment.
Here they all are:
* Some of these techniques do involve joining a club or network for which there is a fee, but actually spending the night each time is free. Besides, those one-time fees tend to cost less than a single night's stay in a mid-priced hotel.