Power is back on, But network problems continue

Power's back on, woooooooooo.

Okay, so I have two problems:
[1] If I attempt to 'send' packets 'from' an IP address that my computer actually has, the host OS's TCP stack sends a RST packet when it sees a SYN/ACK response to my 'sent' SYN packet.
[2] If I attempt to 'send' packets 'from' a different IP address, the packets get bounced back and forth several times between my computer and the router. For whatever reason, the listening server ('nc -l <port>') doesn't respond at all.

Yay.

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