I personally love playing solitaire as a way to pass time on planes and while waiting for meetings to start. After installing Astraware Solitaire on my iPhone 3GS, I erased four other solitaire games that just didn't match up to the quality and variety of play. The new Trophy Deck feature will keep you playing for weeks, trying to collect all of the cards by achieving goals.
Since it's Independence Day here in the U.S., you might also want to download Handmark's free fireworks app, featuring patriotic backdrops, festive fireworks, and music. From all of us here at TUAW, have a safe Fourth of July weekend!