SparkFun COM-09519 8-bit Parallel-Ib/Serial-Out Shift Register – 74HC165N
The SN74HC165N is a neat little IC that will take an input of up to 8 parallel lines and produce a single, serial output. You can even daisychain 2+ together to add even more parallel lines. Its a great way to increase the number of inputs on a microcontroller.
This chip works with a voltage supply anywhere in the range of 2-6VDC, and at clock frequencies of up to 29MHz (@6VDC).
Comes in a 16-pin DIP package.