There have been some colds memorable if for nothing else than the timing, and the timing usually has ruined a ride that was weeks or months in the planning. I've had colds wreck riding the Terrible Two, The Death Ride, the Gold Rush (twice!), the 2004 version of the San Ramon to Malibu multi day ride, and countless club rides.
Am I unique in this among randonneurs? Are brevet riders, ultra distance cyclists, more prone to respiratory ailments? My guess is no, it's just me, but let me know.