If you participate in unwritten envelope swaps, what do you do with the cards people send you? Do you put them in the pool of postcards for future written swaps? Do you save them? Do you do something special with them?
I have received a few and I’ve considered everything from lotteries to round robins with the theme of unwritten envelope swaps.
I simply don’t swap for them. To me a postcard is not complete without a stamp and a message so I only swap written and stamped 
If I swap for postcards I like, I keep them. Sometimes I send them out in the Write Back My Postcards RR (WBMP RR), and then I get them back written.
Sometimes I swap for blank cards, either because I know a Postcrossing friend will really love it or because I can’t find cards of that theme where I live (so I add them to my stash) or because I love them. When I swap them for myself I will get them written + stamped by Postcrossing friends… similar to the WBMP RR.
I sign up for quite a few In-Envelope swaps of Unwritten cards; I also periodically host some of these. The ones I sign up for are for are moderated RRs of specific themes (e.g. Lighthouses, Maps, City Views, etc. that being so, I keep many of the cards I am sent.
Not everybody collects stamped and written cards. If you like Unwritten cards, you can join us with the North America traveling envelope. It’s a lot of fun and we exchange many nice cards.
I collect both written+stamped and unwritten cards (the only thing I don’t like are cards written but not mailed as postcards or with fake stamps), so what I get usually goes into my collection. Those I really don’t like (or duplicates, so far that hasn’t happened) go into my stash for Postcrossing.
@brittanyjewell I am responding to your topic header more than your post. I never swap for or ask for unwritten postcards in envelopes, although sometimes I receive them because either (1) someone misinterprets my request for a written card in an envelope as a request for a letter-plus-a-blank card, or (2) sometimes someone just sends me an extra.
I personally do not collect blank cards. So if the cards are nice (which they usually are) I will prefrentially send them on to a penpal who will like them or will save them to send as an official.
If it is something like a tiny shaped card that I can’t send by German post, I’ll send it as an extra when I am sending a card in an envelope to someone who may appreciate it or be able to pass it on.
I would just use them to sent them written to other people ^-^
Funny. I recently received some unwritten cards and I was considering a lottery as well. 
In a way it’s strange the way I organise the cards I buy for sending, I sort them according to either brand or shop. So when someone sends me unwritten cards, I have no idea how to sort them. 
I’m in a similar conundrum. I sort mine by whichever bundle, box, book, etc. in which the cards arrived. So, the misc single cards I receive from swaps end up in the back of the storage box.
I put them in the stash (for official or not, exchanges).It is nice to see different cards from different people bought from shops you will never visit. And have some variety in order to accommodate more wishes for others. The only thing i dont have any use for, are blank cards with views of places i have never been. I hate sending a card to someone from somewhere i know nothing about… if it is from a trip of mine, it might have a story/a background.
A few of them i keep to put on my wall or collage, but that are specifically exchanges for this purpose.
I do blank swap for 3 reasons:
There is also a tag for this in the old forum. Someone needs to move it to the new forum 
I don’t collect unwritten postcards but I have made the exception when they come with a little note that is interesting, if the cards are really my aesthetic.
I think I’ve only kept them two times?
Since I display my cards so that they show both front and back, I don’t like unwritten that much.
What I don’t keep I usually lottery! Or send in groups.
If they fit with my postcard wall (my real wall in my house lol), I hang them. All others go into my stash to send out. I like participating in these because I can get several cards at once to either keep for myself or diversify what I send out!
Also, I’ve been saving the stamps from the envelopes to send to collectors!
I don’t really do blank card swaps, but some Postcrossers have kindly sent me more than one in an envelope. I will keep some of them, and send the rest to other Postcrossers if I know they will appreciate it better than me.
When I get unwritten cards, I generally use for the Write Ba.ck My Postcard RR.
Hello 
I keep a card that is my favorite and my collection, and for cards that are not included in my choice I will use to swap or send to others and also I will share in the lottery in my postcard group. I think it will be more useful for other friends.
Happy postcrossing
Hi,
I collect Lali and Charis Bartsch cards unwritten to send to my cousin’s kids. I also send them Where’s Waldo/Wally, but those I can buy myself over here, whereas I rely on other Postcrossers for the Lali’s/Charis Bartsch‘s cards.
As for other cards, if I’m sent an unwritten viewcard/country-specific card, I’ll sometimes write lists on the back of what I want to do/see/eat if I’m ever lucky enough to go to those places, or interesting facts I’ve learned about those places.
My faves are non-viewcards, though. I love to write, so if someone sends me an unwritten non-viewcard, I can write possible characters or story plots on the back. I’ve sometimes seen illustrated cards where I’ve thought, “Wow, if I could draw my character, this is what they would look like.” So I sometimes trade for those cards so I can visualize my stories.
I think in all the years I’ve been Postcrossing, it’s only a handful of times that I’ve sent out cards that were sent to me unwritten…and only because I was passing them on to people who had a collection for them and I knew they would love the cards more than I could. 
You could say the same things about stamps - they are meant to be used on mail. But you do know that millions of people collect mint, unused stamps.