Anything with a good or quick beat works for me! I find myself cycling to match the tempo, which helps me keep up a good pace. The only thing I have to be careful about is not singing along, just so I don't run out of breath much faster or get a stitch in my side.
Right now, some of my favorite songs to cycle to are "Catch My Breath" by Kelly Clarkson, "Breathing" by Yellowcard, "White Rabbit" by Egypt Central, "The Fall" by Blue Stahli, a sped-up version of "The Phoenix" by Fall Out Boy, "Blood Sugar" by Pendulum, "Tsuyoku Tsuyoku" by Mihimaru GT, "Clattanoia" by OxT, "Energetic" by BoA, "Atarashii Bunmei-kaika" and "Killer Tune" by Tokyo Jihen, "Across the Line" and "New Divide" by Linkin Park, and "The Receiving End Of It All" and "Would You Be Impressed?" by Streetlight Manifesto. I'm going to make a playlist on my phone with all these songs so they're more readily accessible to me while I'm out on my rides!