Heres an odd one:
I have two computers running in my home.
One is an ASUS WIN7 Home Premium 64 bit laptop with built in wireless. The other is a HP Pavilion Slimline, same OS, with a USB-wireless adapter.
I have a Belkin F7D5301 v1 router. DHCP, WPA-Personal PSK. The firmware is up to date according to the built in firmware utility.
The desktop PC (Pavilion)is always on. The laptop is on when I need it.
When using just the desktop PC, everything is kosher.
When I use the laptop and connect to the router, the connectivity drops. Not only drops from the laptop, but the SSID broadcast of the router literally disappears. It cannot be found in the wireless search of the laptop, desktop, Wii, X-Box, or my phone. The only way to get it to reappear is to either power cycle the router, or change the laptop over to my neighbors unsecure router for a brief moment. At that point, the broadcast of my router magically reappears. Connect to my router again with the laptop, and *poof*, broadcast disappears again.
I have done a hard reset on the router, but no dice.
It would seem that there is a correlation between my laptop and the issue, but beats me as to what it could be.