I assume you are talking about a single slide, rather than a group exchange,.
Should be a bit cheaper to mail, as compared to the postcard and group exchanges .
Hm, that's not what I assumed. Art, enlighten us... My thought was: if 36 people sign up (and we don't make groups), then I can shoot one roll of K64 (assuming all shots will be worth to look at, ahum...), send 35 slides to 35 participants and keep the 36th for myself.
If it's only one slide that I have to send and only one that I will receive, then I doubt whether I would participate.
-- A sinister little midget with a bucket and a mop / Where the blood goes down the drain --