I have to commute every day on one of the worst interstates in the south; it seems that there is always some construction or a wreck somewhere, especially when it's time to drive home in the afternoon.
I found these apps to help check traffic conditions: INRIX traffic and Traffic View. The first shows the road map and where any congestion and/or construction and wrecks may be (this is just the free version, the paid version has cameras). The second shows all the traffic cameras in you area in real time (the $5 version). These are really helpful to me.
I am also an avid photographer, so Hipstamatic, Picture Show, Pano, and Gorillacam are all on my list. I also use iLoader lite, Darkslide, and flickr sendr for easy uploads to Facebook and Flickr.
I love talk radio when I'm driving somewhere, so if I'm not listening to a podcast, I use HiDef Radio, for music Pandora is good, and I also like Public Radio.
I don't play many games, but Gemmed, Superball, Topple, Moonlight Mahjong, and Bejeweled are fun.