Well I don't keep cool numbers, but I do keep all stars. Well - all except the $100 dollar star notes.
well i do have two $100 star notes but if the times get tighter i will spend them, i will miss the one that comes from a run of 320,000 it's a 2003 DB0030----*.
Well, I keep alot of different serial numbered bills - semi-solids, ladders, book-ends, low numbered serial, etc. Probably the one I like the most right now that I have in circulated condition is a Series 2003-A $1 with the following serial number - E 00000376 G That is probably the lowest serial number bill that I currently own. Not in CHCU but hey..... Smaugy...
i keep serial numbers that are collectible.. but i dont bother with coolnumbers.com notes lol to me, it just a gimmick. its fun, but has little if any collectible value.