Is there any such device to increase the signal strength - just set up a system in a house with 3' thick walls - you get the picture !

Here's an interesting discussion regarding such inquiries: http://forum.ecoustics.com/bbs/messages/8829/56508.html

3" think walls, is that dry wall of brick?

Most of the time a change to a pig tail should sort it out, but some times you need just to move about 5" and it all works fine..

the angle of attack needs to be straight not at say 45o as a 3" wall becomes about 6"

I have a question... There is a network in my neighborhood, a wireless one. My internet is not working cuz the mode is fooked, but is there a risk of me being caught for being connected illegally to a someones else network?

If they ever look at there wireless network Status and see you connected yes. Or notice a slow down in connection and bust you yes.

But as far as I know, if a network is NOT secured with a Key, or anything, its not illigal to connect to it.. atleast you wouldnt think so. I can say as I wouldnt try an press charges on someone if they had connected to my wireless network, when it was my own dumb fault for not making it secure.

As far as the wireless signal boost, I used a wireless repeater. it works great
I live in a Skyline Moble home, 70ft long, thick walls. when I placed a wireless repeater in my room with my PCs up on the wall, Ive never been disconnected. since.