Neil Patrick Harris & Felicia Day - My Eyes (OST Dr. Horrible's Sing-Along Blog)
Felicia Day & Neil Patrick Harris - Laundry Day (OST Dr. Horrible's Sing-Along Blog)
Neil Patrick Harris, Felicia Day & Nathan Fillion - A Man's Gotta Do (OST Dr. Horrible's Sing-Along Blog)
Felicia Day & Neil Patrick Harris (OST Dr. Horrible's Sing-Along Blog) - My Eyes