Murder Train (From "How I Met Your Mother: Season 3") — The Foreskins
The song that Robin's ex, Simon, "made" and gave to Robin to play on her radio show. This particular song becomes a recurring song throughout the show, in times of anger and stress within the gang.
Sandcastles in the Sand (From "How I Met Your Mother: Season 3") — Robin Sparkles
Robin's second single that she released as "Robin Sparkles". played at the end of the episode when Barney and Robin watch the music video, before sleeping together.