Okay, first off, I hate duct tape. Gaffers tape is where it's at. I can't imagine that the slickness of duct tape wouldn't cause the wallet to squirt out of my hip pocket all the time.

Second, I thought I'd try something a little different than the norm. Here's what I've found so far:
Resist Today (art print)
Big Skinny (thin)
Super Slimmy (thin)
All-Ett (thin, eco-friendly)
Alchemy Goods Franklin (alternative materials, eco-friendly)
Used Rubber (alternative materials, eco-friendly)
Stewart/Stand (alternative materials)
RaggedEdge (alternative materials)
Carbon Fiber Gear house brand (alternative materials)
Rogue Wallet (nonstandard design)
Mighty Wallet (alternative material, art print)
DIFRwear (alternative materials)
Stretch (nonstandard design, minimalist)
Money Band (nonstandard design, minimalist)
NilesZ (hard case, art print)
Jimi (hard case, eco-friendly)
ACM (hard case, alternative design)
Cassette "wallet" (DIY, hard case)
Keyboard printed circuit wallet (DIY, alternative materials)
various DIY wallets (DIY)

Comments about those: I don't want a front-pocket wallet; my front pockets are already filled. I don't want a hard case wallet; I don't want to sit on a solid lump. I'm questioning of the durability of rip-stop nylon as a wallet material; I'm even more questioning of its non-tackiness. I'm questioning of the durability of stainless steel mesh as a wallet material. I'm concerned about some of the wallets having pockets that seem less than fitted to a regular credit card.

Failing something kinda wacky like one of those, I'd like something super-traditional, but maybe slightly quirky. This Ettinger wallet exemplifies those criteria, though it would leave me with little to put in it.

In general, I tend to prefer a large bifold wallet. For the record, this is my current wallet. (Though I'm pretty sure I paid nowhere near list price for it.)

Things I dislike include: showy logos, especially external ones; "flip"-type wallets, where it's designed like a bifold, but with an additional flap sewn on as if an afterthought; positive closures, like snaps, zippers, velcro, etc.; nylon exteriors. I'm sure there's more.

And, in case someone can find one of these for me, there's a style I've been lusting after for ages; an acquaintance of mine used to have one. When folded, it's the size of a traditional bifold wallet, but there are three sections. I'm pretty sure that it was a European-style checkbook wallet, and the third section had a band on it to attach one's side- (that is, not top-) bound checkbook to. It provided a large number of card slots, but since you didn't have to open it up all the way, the less used ones were kept hidden. I'm pretty sure he told me he got it in Brazil, but I might be totally misremembering that.