Odd... my internal network address (I have a LAN with my brother now) is 169.254.x.x. Or is there a few different versions?
Likely enough there are. I believe 10.x is an invalid range out on the Internet, too, or at least part of it is.
Yep. Three blocks of addresses are reserved for "private networks" (such as home lans, etc):
10.0.0.0 - 10.255.255.255
172.16.0.0 - 172.31.255.255
192.168.0.0 - 192.168.255.255
Additionally, the network 169.254.0.0 - 169.254.255.255 is reserved for "auto IP" configuration. Basically, if a client is supposed to get its address from a server but no server can be found, it will automatically pick an address in this range. It's supposed to retry getting a "real" address until a server is found.
Finally, 192.0.2.0 - 192.0.2.255 is reserved for testing. All of the above are not routable on the internet itself.