Rare Fed Reserve Banks?

The rareness depends on the series and where you live. When you reside in a particular district you see a lot more notes from that district because that is (for the most part) where your banks get their cash. Then every series differs in the amount of notes printed per FRB as determined by the BEP. I couldn't even begin to tell you how they come up with the number to print, I think they throw a dart at a map or something.

Is there a currency link regarding serial numbers people tend to look for. I save old bills, but I wasn't aware beyond star notes that certain serial numbers are sought after by some collectors.