Since I work in the finance industry, my HP 10B II Financial Calculator is a must have. I seriously use it every day. It comes in a faux-leather cover, and fits comfortably in my hand, meaning that I can take it everywhere. There are lots of keys on the 10B II that will not make sense unless you know what you are looking at, so if you choose to buy one it is imperative that you read the users manual. Basically a financial calculator is different from a standard calculator because it allows you to perform Time Value of Money calculations. This means that you can discount cash flows to find either the present value of cash flows at some point in the future, among other things. This is not a calculator that will appeal to everyone. In addition to work, I use it to determine how much money my various investments will have when I retire, assuming a standard rate of return. If that's not something that you find fun to do in your spare time, then I would not buy this calculator. You can get one that does much less for cheaper. However, as far as "specialty" calculators go, this one is pretty reasonable. I bought mine for $30, and since I use it every day, I have gotten a great return on investment!