Secret Song!
This Gameshark/Codebreaker code is the only way to unlock the secret song "*Trippolette", by "Andrew Buch." It has the hardest section in the game (harder than the end of Bark at the Moon), but the overall shortness of the song makes it beatable.
The code will replace the bonus song "Guitar Hero" in the setlist screen (and shop) with Trippolette while it is active (when you reset, the Guitar Hero song is back).
The code is very long (33 lines), and is as follows:
(M)ust Be On
F0273744 00273747
Bonus Song
2044CD38 64612F73
2044CD3C 72616876
2044CD40 796E6F6D
2044CD44 7664612F
2044CD48 6D726168
2044CD4C 00796E6F
2044CD54 64612F73
2044CD58 72616876
2044CD5C 796E6F6D
2044CD60 7664612F
2044CD64 6D726168
2044CD68 2E796E6F
2044CD6C 0064696D
205CBAF0 6E656857
205CBAF4 646E4120
205CBAF8 73692079
205CBAFC 2074276E
205CBB00 6B636168
205CBB04 2C676E69
205CBB08 20656820
205CBB0C 706D6F63
205CBB10 7365736F
205CBB14 20746120
205CBB18 6B726542
205CBB1C 0065656C
205CAD20 00796F4A
20545760 72646E41
20545764 42207765
20545768 00686375
205459D0 6972542A
205459D4 6C6F7070
205459D8 65747465
Have fun with it!