we still have some smalls of the shirt-- if that's your size i can help you out, but otherwise they're all gone. we gave them to anybody who bought a pair of the shoes for as long as they lasted.
as for another SLAP shoe, it doesn't seem likely right now. companies just aren't really doing fringe product stuff as much these days, and with the time it takes to develop and produce a shoe, especially the way adidas did it through feedback on the site, you probably wouldn't see it for almost a year or more anyhow. keep posting ideas if you'd like, all the shoe company people likely know about the thread already and they will contact me if they are interested in doing something. i can also go to them if there is some kind of consensus on what shoe/model is most desired, but really i wouldn't hold my breath on anything right now.