Computer keeps looking for an invalid IP address: Invalid ARP Entries

The lights on my router kept blinking every few seconds even when I
wasn't doing anything on the computer so I got curious and loaded up
Ethereal. Every couple of seconds my computer sends out a broadcast
ARP packet that says who has 192.168.1.3 Tell 192.168.1.2 (my
computer's IP address).

I looked in the Hosts file, ran IPConfig, ran NETSH DIAG, looked in the
Network Shares, etc. and can't find anything that has the address
192.168.1.3. Any idea why it would be doing this?

I did look in the APR table and 192.168.1.3 shows up with no physical
Address and Type Invalid. I deleted it from the table and it shows
back up again.

I realize it's probably not effecting anything but tracking down wierd
problems is one way I learn a whole lot more