Bizzare but fun link of the day

Telephone Touch Tone Tunes

Now you too can play "Joy to the World" on your phone.  Just be careful of any tunes that start with '1'...

With two-tone dialing, you get (roughly) the notes F, G, A, and B-flat on the rows (starting with 1, 4, 7, and *, respectively) and the notes D, E, and F-sharp on the columns (1, 2, and 3 respectively).  Chords are created by combinations thereof:

1 = D over F
2 = E/F
3 = F#/F
4 = D/G
5 = E/G
6 = F#/G
7 = D/A
8 = E/A
9 = F#/A
* = D/Bb
0 = E/Bb
# = F#/Bb

Because the notes are not exact, there is a bit of leeway regarding sharps and flats and so forth.

Reference:
Tone Dialing
Frequencies