I miss that too. I feel it was a part of my learning experience about vintage components. Following certain bidders really opened up my eyes to the really rare stuff and watching people build up groupos appropriate to specific eras and bikes was neat. It was also fun to see where in the world the stuff was going and also to figure why it went for as much as it did. Tons of fun!
I've noticed over the years that certain components come and go in waves. Following bidders sometimes let me get in before the market exploded and the prices skyrocketed. I REALLY miss that! Seems to me that once some specific part goes for a good chunk of change the market gets flooded and the prices start climbing even more. Two examples on my watch list that have done that are Campy Ergal freewheels and Avid Arch Supreme brakes...Started low and now they're triple the cost of a year or two ago. I got my freewheel for cheap (IMO) outside ebay but I'm afraid I'll have to pay big time for the brakes 'cause I didn't catch the wave. Vintagesque (mid school) high end MTB parts are skyrocketing big time and early BMX stuff has already gone through the roof...
Titron pedals anyone?