Hi

Supposed I logged on to my neighbours broadband connection with my Wireless.

Would there be any security risks?

Would they ever know someone is connected on to it?

NB: This is for access- not for anything illegal. Because of my wireless set up I need my desktop PC to be turned on to access the net- whereas the neighbour keeps theirs on all night.

Thanks

Yes they can find out, because most system have loggers that shows what computer connected at what time (in some it needs to be turned on). However, it does not look like they are sophisticated enough to find out; otherwise, you would not have been able to connect to their with their permission (or maybe they are trying to test you!?).