Driving a simple speaker with an Arduino

Not that there was much to the project, but in efforts to bring some basic audio skills into my toolbox, an 8ohm speaker was purchased and hooked up to an Arduino Rev3 via a 100ohm resistor.  The parts are listed below:

[Mouser 253-CE405-RO] Kobitone 8ohm 1.57" Speaker
[Mouser 291-100-RC] Xicon 100ohm Carbon Film Resistors

Two 22AWG wires were soldered onto the speaker, making it ready for use.

The code used to drive the speaker is fairly simple as well; Here are links to the original material I used as reference:

Arduino Tone
Arduino Play Melody