Liberty $5 Mintmark Set
Due to the longevity of this series, there are countless ways to put together a classic 7-mintmark $5 Liberty set, ranging from relatively easy to essentially impossible (if you insisted on including the 1854 as the San Francisco specimen, for example). Now that I think about it, it would be an interesting math problem to calculate exactly how many such sets could exist - I would guess the number is truly staggering. I suspect lots of people who collect these small but cool sets have one or more "special interest" features. In my case, I wanted to include all three of the 1839 issues (Philadelphia, Charlotte and Dahlonega), which have a slightly different portrait style than the rest of the series, not to mention the neat "C" and "D" obverse mintmarks. I finally got my 1839-P crossed from NGC to PCGS so I could include it in my online set:
I've seen the 7-mintmark set discussed here before, but would enjoy seeing other examples if you have them.