Tango - allows me to keep in touch with my best friend who will be deployed oversees next week, and will have his cell service shut off. The app allows you to talk, text, and share videos and pictures!
Weather Bug and My Radar - each has its advantages
Around Me - you can search for local businesses by either name or category. It doesn't show everything, but it's not bad for the price.
ShopSavvy - allows you to search for products. Results list online and store retailers in order of price. Many products searches also contain product descriptions, reviews, and other related items.
Seconds - is a programmable interval timer. Only the Pro-version allows you to save, import, and share timers.
Dragon Dictation - your own stenographer. Surprisingly accurate.
Brit + Co. - Offers a host of creative ideas for interior decorating, fashion, planning parties, etc.