All the games I know about allow only a single online player per PS3. The number of PS3s that can go online from the household depends more on the capability from your internet provider because the PS3 and the PlayStation network would have no problem connecting multiple PS3s from the same location.
Resistance 2 can have online co-op play from the same PS3, Warhawk and LittleBigPlanet may also allow more than one player on the same PS3 see related links
No
No.
sadly not it would be grate
Nope
yes you can play 2 players online on world at war on the same ps3 screen
You only need multiple Gold accounts for Xbox One if players wish to play at the same time. If players do not wish to play at the same time they can share one account.
On the same system you can have 7. online it depends on the game
No
Some games, like Halo 3, allow 4 players to play online at the same time on one console, but most game do not allow multiple players online at a time on the same console.
No. PS3 and Xbox has different servers.
Yes, you can have two car insurance policies in the same household but it would probably be cheaper if you just went with one company instead. Most auto insurance companies offer a multiple car discount.
i have tried this my self, you cant sorry.