Lotta bang for your buck!

I bought the TI-34II to to help out in my college Intermediate Algebra class, and the thing has been wonderful.

It's absolutely loaded with features - probably one of the best you're going to get without buying a graphing calculator.

It has a 2-line display, allowing you to see your answer without losing the problem it goes to.
Unlike your "basic" calculator, the 34II allows you to enter in, and see, an entire string of computations at once, and you can edit, delete, and insert items at any time. A memory function allows you to scroll back through past computations to bring back one you did previously.

One of the things that I've found particularly helpful is that you can work directly with fractions - you don't have to worry about converting everything to decimals first. Simply enter your computation using fractions, and it will give you a fraction back. Fractions can then be automatically simplified, or changed to decimal form. (And decimals can be automatically changed to a fraction as well).
Also, the calculator understands the correct order of operations, and also allows the use of ()'s.

The TI-34II also works with angles, has trig and stat functions, variables that you can save numbers under, the ability to store and recall custom operations, scientific notation functions, and more.

Although one or two other reviewers mentioned that they had trouble with the buttons responding, I've never had a bit of trouble, and in fact no matter how fast I hit the keyboard I can't get it to fail - I've tried just to see if I could do it. The only time it won't respond is if I've hit two keys at once - a situation where you probably don't want it to just guess which one you're hitting anyway.

The calc comes with a protective cover that slides on and off pretty easily but not so easy that it slides off, and a handy reference card slides into a slot inside the cover.

The only down side I've found is that many of the more "advanced" functions (such as trig) have to be accessed by going through a menu, you can't just hit a key for them. Not a problem in my case as I don't use them anyway, but the issue is there.

Overall, a great product for my $20.