Twenty of the cards are on a 'cat' theme. Joan has designed the cards around words or sayings that incorporate 'cats' in some way - eg cat on a hot tin roof, octopuss, cat's got the cream etc. She's used lots of different techniques and backed them with pelmet vilene.
As with the ATCs, the only 'rule' about fabric postcards is that they should measure 6"x4".
If you want to know more about fabric postcards have a look at http://www.squidoo.com/fabricpostcards/#module1500105 there's loads of information.
The nice thing about making postcards or ATCs is that you can work on a small scale and they can be quite quick to make.
Both formats are becoming very popular all over the world and the concept is based on the picture cards that used to come in cigarette packs or PG Tips tea. And the idea is to make them and swap them (like we used to do with our spares!) - 'trading' has nothing to do with selling them.
Here's some more of Joan's postcards -
(Thanks Joan - you've created a lot of interest!)