The Straight Dope message board is the web page I visit the most often, but I think that’s considered a given here.
Many of my faves have already been mentioned, so I’ll go for the more personal ones.
Other websites I’ve been going to frequently of late:
Audiology Classifieds. What can I say? I’m looking for a more permanent job right now.
Roger Ebert’s Movie Reviews. I like his well-written reviews, but jeez, he keeps giving so much stuff away in the plot that, if I plan to see the movie, I don’t read them until after I see the movie. I’ll look at the star ratings, though.
Age of Empires II: Age of Kings Game Room. I confess. I’m horribly addicted to this game. I’ve been cutting back lately, because I want to devote more time to writing.
Mapquest. It was mentioned in the OP, and it deserves mention again. This site rocks. I’ve used this often.
KGW-TV’s Traffic Reports. I always check the traffic reports before I leave work at the end of the day. It’s nice to know ahead of time if the Sunset Highway is FUBAR, and I can take my alternate route.
Weather in Lakeland, FL. Where I lived until I was ten years old. I still have many relatives living there, and occasionally I’ll look up the weather report here (especially during the summertime) and remind myself of why I’m glad my family moved to Oregon.
Weather in Hillsboro, OR. To hell with the weather reports on the local news, where they like to spread their information over a commercial break or two. I can get the information I’m interested in much faster here, thank you.
The Digital Bits and The DVD Review. I want to know if the DVD I have my eye on is worth it.