
I usually sit on the couch with my laptop when I register postcards - from Swap-bot, Postcrossing, etc.
Soda usually sits next to me and keeps my postcards warm.
If she's still on them when I get up, I let her keep them for a while... hence there are usually postcards on the couch.
See more excellent mail cats in the Feline Postal Brigade Flickr photo group... and please submit your own!