strobist info: Nikon SB-24 speedlight at 1/4 power, about 25' away from subject, positioned at camera left, held by my wife acting as a "voice-activated lightstand". I synched the flash with Pocket Wizards.
More photos from the Amgen Tour of California prologue here.
Learn to light at Strobist.
(edit) Sorry about dropping the EXIF info - Camera Settings: shot with Canon 40D; ISO: 200; Shutter speed: 1/50; Aperture:6.3; Lens: Canon 17-85 @56mm; The slower shutter speed allowed for the panning effect, the flash burst on Lance froze some of the details.