A few months ago my brother-in-law gave me a very thin wallet. It's made of kite material (rip-stop nylon it says on the website) so it's light, thin, and tough. So today I was browsing the company's website and saw their traveler model. It basically takes out the stitching from one side turning two credit card pockets into one larger pocket, and then enlarges the whole thing a little bit, with the idea that you could stick your passport in there. Hence the "traveler". Anyway, it looks to me like that pocket would fit some 3x5 cards just perfectly. So then you'd have a thin, minimalist wallet that also holds your Hipster.
Currently I'm trying out simply keeping my pierced hPDA sandwiched inside the wallet since that's what I've got. But I thought the greater hPDA community at large might find that "traveler" wallet an interesting option.