Toulouse is a city in southwest France.
The metro has a system of barriers at the entrance. It's easy to jump over them, but in some of the bigger stations or termini, there is human guard dogs at work to make sure you don't. However it is good to know that tickets are valid during 1 hour after the first punch. That means the trash bins are full of valid tickets ;)
Toulouse has an unfortunate lack of cheap hostels, so if your not couchsurfing then it can be an expensive night. There is nice roof to sleep on near the main train station. Walk along the street that runs in front of the station in the same direction as the traffic for 150 metres, before you come to an intersection and a bridge over the canal. On the corner to your left there is a roof which comes quite low, almost to head height. Its easy to hop on here when pedestrians are few, and then get further up on to the main roof. Totally out of view from the street, and with some nice soft gravel and even a bit of shelter. Not the quiestest spot but it beats 40 euros.
Alternatively, try sleeping in the train station. It officially closes at 1am, that's when the guards kick all the homeless out. After saying that she had a train ticket for the morning, the guards showed mercy on Kimmietaylor28 and let her sleep in a very warm room at the back. The station opens again at 4am, but those three hours of free sleeping were useful.
Update, Wed 18/03/2015: At least today, the train station closed at midnight and opened at 5:30. You can sleep there if youre a woman or if you have a train ticket, if not, tough luck. There is a nice and relaxed, albeit a bit run down place at place arnaud bernard though, were you can spend the night with a beer or two until the station opens again.
If you don't have a smartphone or this kinda STUFF and still need to access internet, go to the Médiathèque José Cabanis, a very big building very near to Train and Metro Station Marengo. There, just ask at the info desk and they will give you a card with which you can access internet on the computers there for 1,5 hour, for free! You'll just have to wait 15 minutes for the card to become valid, but as there are so much things to read (loads of international press!), you won't get bored at all! (and there is air-conditioning :)) Open everyday except monday.