OT computer help: my wireless network disappeared

[JTG51]

I have a wireless router and a laptop with a wireless card. It's worked fine for months. Today, it won't work. I haven't changed anything.

My network isn't listed in the wireless network connection window. When I click 'refresh network list' my neighbor's network shows up, but not mine.

I can still connect just fine if I plug into the router.

Anyone know why this might happen, and how I can fix it?