Google Goggles was neat - but I really didn't get to use it in the way I really want to - with landmarks and art. I'm looking forward to trying it on a trip to Washington DC this spring. :) The same goes for Wi-Fi Finder. That will be handy when I travel. Right now? Not so much. LOL
Internet Browsers: I am a big fan of having multiple browsers handy in case one quits working or doesn't display well with the content. But when it comes to preferences, I love Chrome. It's clean and seems to be the most compatible with up-to-date websites. I also use a lot of other Google tools and it's a good match.
Another app that others might find useful: SoundHound. Users can have it "listen" to a song on the radio or even hum the melody to identify it.