Dude recorded a whole Jonathan Coulton concert on his cell phone and posted it to YouTube. All I've heard so far is Coulton's acoustic folk cover version of Sir Mix-A-Lot's classic, "Baby Got Back."
Jonathan Coulton in Seattle - 03 - Baby Got Back [youtube]
Coulton's own classic, "flickr," which the kid calls "the grandma song"
Also, "Stroller Town," Coulton's ode to the Bugaboo
Buy something musical at Coulton's site; those Bugaboos don't pay for themselves, you know [jonathancoulton.com]
And finally, DT's own foray into song: "Baby Got Biodiesel"