I was on my first go-round at NAHBS 07 when I rounded a corner and came face to face with Tom Ritchey's bike that he built back in 1974. It stopped me dead in my tracks. I first saw photos of it in an early Rivendell Reader and just marveled at the minimalist aspect and attention to detail. It's what a purpose-built racing bike should be. The dual-plate fork crown with open-top legs makes the assembly look trick and light, the rear brake cable routing thru the seattube uses no extra cable housing or ferrules, the delicate drop-outs with gussets and drilled hanger show strength and style.
Overall, the appeal to me is a no-nonsense, innovative, elegant machine that show-cased Tom's brilliance back in the day.
But the most important aspect of this bike was that he built it for his Dad.