That should technically read "720, give or take", but it just doesn't have the same punch.
Anyway, I counted the cards, people. Well, the envelopes. 720, yo. SEVEN HUNDRED AND TWENTY. There were many envelopes with multiple cards and notes, so I don't know what the "real" number is.
So, I have completed Step 1 of the curating: physically sorting the envelopes into the states and countries of origin. Yes, I sorted them alphabetically by state, and then alphabetically by city within each state. I DO NOT HAVE OCD. I'm just thorough. Ahem.
Step 2: enter every envelope onto a map on Google Maps. Behold my skills! (Apparently I have no skills -- I'll fix this. Eventually.) I've done all the international ones, and Alabama through Maryland.
Step 3 will be sorting the notes themselves by medium: postcards, regular cards, post-its and similar, and artwork. I figure that'll make Step 4 (storage/scrapbooking/framing/what-have-you) easier for you lot to figure out. Right? I mean, one of you has a brilliant idea you're just sitting on, waiting for the right moment. Well, you have some time, my invisible friend, but it won't be for long.