I have this weird problem where sometimes I don't have access to google.com on my home computers. This include most of the Google sites - maps, calendar, docs. I sometimes get a plain error page, sometimes even a weird Yahoo! error page (weird I know, especially as I have never used Yahoo).
This problem happens every now and then, a few times a day for anywhere between 1 min to an hour. It happens both on the Wi-Fi network and when connecting with a wire to the modem.
What can cause this problem? It's so frustrating.