If you loved the William Wallet and its minimal two-metal-sheets design, you'll probably be just as enthused about the Omega Titanium Wallet, a similarly-styled cash and card holder with a sleeker, more efficient design.
Made by Fireti, it uses a pair of titanium sheets held together by EPDM rubber O-rings slotted around torx screws that protrude slightly out of the sheets. Like the William Wallet, you hold your cash and cards sandwiched between the metal sheets, keeping them secure in a single pile in your pocket.
Sized (w x h) similar to a credit card, the Omega Titanium Wallet can hold as many 30 credit cards comfortably, although it can be used to carry as many as 50 (albeit, with some discomfort on your part). It requires a minimum two cards inside to use for carrying folded bills (the cards, basically, fill out the gap). A cutout in the bottom of the sheets act as the finger slot so you can slide the cash/cards out of the wallet. When emptied, the same cutout can also double as a bottle opener.
While the primary wallets are made of titanium, they also offer a cheaper version that uses sheets made out of aerospace-grade aluminum. You can get the wallets plain, engraved (four designs available) or anodized (four colors available). Each wallet will come with three sets of additional O-rings, just in case they get damaged.
Currently a Kickstarter campaign, pledges for the Omega Titanium Wallet start at £45 for the version titanium and £25 for the aluminum model. Shipments are slated to roll out beginning April.