I decided to do an arrangement of the song "Happy Birthday to You" for my music teacher's birthday and, after much struggling, this is what came out.
I played and recorded it on my keyboard (a Yamaha Motif XF), then used SoX to convert the file.
Speaking of conversion, you can download the file converted to OGG format here.
This performance is released under the Creative Commons Attribution 3.0 Unported License.